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<h1 align="center">Diablo II Item Format</h1>
<h3 align="center">for Diablo II v1.13d Expansion Set: Lord of Destruction</h3>
<div align="center">Updated June 23, 2012<br/></div>
<p>This file was originally written by Trevin Beattie, whose site is no more (his latest version of this file is available
<a href="https://web.archive.org/web/20161225040510/http://web.archive.org/web/20070829095341/http://www.xmission.com/~trevin/DiabloIIv1.09_Item_Format.shtml">here</a> though).</p>
<h3>Welcome!</h3>
<p>Thanks for showing an interest in my Diablo II Item Format page. While
you're browsing, be sure to check out the preview of my <a href="https://web.archive.org/web/20161225040510/http://www.xmission.com/~trevin/DiabloIIv1.09_Editor.shtml">game
editor</a> for unix+Motif. I currently have the item editor in
development!</p>
<h2>Introduction</h2>
<p>Having searched the web, I found very few references to the Diablo II
<tt>.d2s</tt> file format, and most of them covered the old (pre-1.08)
version. Diablo II v1.09 has significantly changed the file format.
I have started another page which details <a href="Save_File_Format.xhtml">the
layout of the major parts of the <tt>.d2s</tt> file.</a> This document
focuses specifically on the item structure &#x2014; all those pieces of the file
tagged &quot;<tt>JM</tt>&quot;.</p>
<p>Rather than describe everything in terms of byte offsets, I'm going to define
the layout as a series of variable-length bit fields. This is a critical
part of the item format, because the position of many of the fields can change
depending on what comes before it. If I say a certain value is a 3-bit
field starting at bit position 150, for example, this translates to bits 6 and 7
of the byte 18 and bit 0 of byte 19 in the data structure. You can read an
arbitrary bit field programatically using the following code (in C):</p>
<pre>#define read_bits(start,size) \
    ((*((unsigned long *) &amp;data[(start) / 8])
      &gt;&gt; ((start) &amp; 7)) &amp; ((1 &lt;&lt; (size)) - 1))</pre>
<h2>Item List Header</h2>
<p>An item list begins with the following simple header:</p>
<table width="100%" border="1">
<tbody>
  <tr>
    <th width="10%">Byte Position</th>
    <th width="10%">Size</th>
    <th>Contents</th>
  </tr>
  <tr>
    <td align="middle">0</td>
    <td align="middle">2 <tt>char</tt>s</td>
    <td>Identifier string &quot;<tt>JM</tt>&quot; { 0x4A, 0x4D }</td>
  </tr>
  <tr>
    <td align="middle">2</td>
    <td align="middle">16 bits</td>
    <td>The number of items your character has. This does not include
      gems or jewels which have been glued into socketed items.</td>
  </tr>
</tbody>
</table>
<p>Your item list ends with another 4-byte structure similar to the above,
except the second field is zero (i.e.,
{&#xA0;0x4A,&#xA0;0x4D,&#xA0;0x00,&#xA0;0x00&#xA0;}).</p>
<p>In the Expansion Set, your hireling has his/her own item list. This
list is separated from yours by the 2-character identifier &quot;<tt>jf</tt>&quot;. This is
followed by an item list header for the hireling, and then his/her items.
The second item list is <i>not</i> terminated with the same 4-byte structure as
the first; instead, it is followed by the 2-character identifier &quot;<tt>kf</tt>&quot;.</p>
<h2>Item Structure part 1: Simple Items</h2>
<p>There are still many fields in the item structure which I haven't figured out
yet, but I'll leave placeholders for them in case I find out what they mean in
the future. All sizes are in bits unless otherwise specified.</p>
<table width="100%" border="1">
<tbody>
  <tr>
    <th width="10%">Bit Position</th>
    <th width="10%">Size</th>
    <th>Contents</th>
  </tr>
  <tr>
    <td align="middle">0</td>
    <td align="middle">2 <tt>char</tt>s</td>
    <td>Identifier string &quot;<tt>JM</tt>&quot; { 0x4A, 0x4D }</td>
  </tr>
  <tr>
    <td align="middle">16</td>
    <td align="middle">4</td>
    <td><i>unknown</i></td>
  </tr>
  <tr>
    <td align="middle">20</td>
    <td align="middle">1</td>
    <td>Item has been identified</td>
  </tr>
  <tr>
    <td align="middle">21</td>
    <td align="middle">6</td>
    <td><i>unknown</i></td>
  </tr>
  <tr>
    <td align="middle"><a name="27">27</a></td>
    <td align="middle">1</td>
    <td>Item is <a href="#sockets">Socketed</a></td>
  </tr>
  <tr>
    <td align="middle">28</td>
    <td align="middle">1</td>
    <td><i>unknown</i></td>
  </tr>
  <tr>
    <td align="middle">29</td>
    <td align="middle">1</td>
    <td>This bit is set on items which you have picked up since the last time
      the game was saved. <i>Why?...</i></td>
  </tr>
  <tr>
    <td align="middle">30</td>
    <td align="middle">2</td>
    <td><i>unknown</i></td>
  </tr>
  <tr>
    <td align="middle">32</td>
    <td align="middle">1</td>
    <td>
      <div>Item is a <a href="#ear">Player Ear</a></div>
      <div><i>Thanks go to Mike of Denmark for identifying this bit.</i></div></td>
  </tr>
  <tr>
    <td align="middle">33</td>
    <td align="middle">1</td>
    <td>"Newbie" item. This bit is set on the weapon and shield your
      character is given when you start the game. Apparently, this gives
      the item the property of having a repair cost of 1gp, as well as a sell
      value of 1gp.</td>
  </tr>
  <tr>
    <td align="middle">34</td>
    <td align="middle">3</td>
    <td><i>unknown</i></td>
  </tr>
  <tr>
    <td align="middle"><a name="37">37</a></td>
    <td align="middle">1</td>
    <td>
      <div>Item is simple (only 111 bits {14 bytes} of item data)</div>
      <div><i>Thanks go to Guillaume Courtin of France for discovering the
      meaning of this bit.</i></div></td>
  </tr>
  <tr>
    <td align="middle">38</td>
    <td align="middle">1</td>
    <td>Item is Ethereal (Cannot be Repaired)</td>
  </tr>
  <tr>
    <td align="middle">39</td>
    <td align="middle">1</td>
    <td><i>unknown; this bit is 1 on the items I've looked at</i></td>
  </tr>
  <tr>
    <td align="middle"><a name="40">40</a></td>
    <td align="middle">1</td>
    <td>Item has been <a href="#personalized">personalized</a> (by Anya in Act V)</td>
  </tr>
  <tr>
    <td align="middle">41</td>
    <td align="middle">1</td>
    <td><i>unknown</i></td>
  </tr>
  <tr>
    <td align="middle"><a name="42">42</a></td>
    <td align="middle">1</td>
    <td>It looks like this bit indicates the item has been given a <a href="#runeword">Rune Word</a>.</td>
  </tr>
  <tr>
    <td align="middle">43</td>
    <td align="middle">15</td>
    <td><i>unknown; some of these bits may be set</i></td>
  </tr>
  <tr>
    <td align="middle">58</td>
    <td align="middle">3</td>
    <td>
      <div><a name="58">Item location.</a> Actually, I have only seen a few
      values for these bits, so I'm not 100% certain of its validity. If
      you see any other value here, let me know what it is and where the item is
      located.</div>
      <table cellspacing="0" width="80%" align="center" border="1">
      <tbody>
        <tr>
          <td align="middle" width="20%">0</td>
          <td width="60%">Item is stored (see <a href="#73">bit field 73</a>)</td>
        </tr>
        <tr>
          <td align="middle">1</td>
          <td>Item is equipped (somewhere on your body)</td>
        </tr>
        <tr>
          <td align="middle">2</td>
          <td>Item is tucked in your belt (or sash)</td>
        </tr>
        <tr>
          <td align="middle">4</td>
          <td>Item is being moved (i.e., has been picked up by the mouse).</td>
        </tr>
        <tr>
          <td align="middle">6</td>
          <td>Item is glued into a socket.</td>
        </tr>
      </tbody>
      </table>
    </td>
  </tr>
  <tr>
    <td align="middle">61</td>
    <td align="middle">4</td>
    <td>
      <div>If the item is equipped, this field tells where it is. Possible
      values are:</div>
      <table cellspacing="0" width="80%" align="center" border="1">
      <tbody>
        <tr>
          <td align="middle" width="20%">1</td>
          <td width="60%">head (helmet)</td>
        </tr>
        <tr>
          <td align="middle">2</td>
          <td>neck (amulet)</td>
        </tr>
        <tr>
          <td align="middle">3</td>
          <td>torso (armor)</td>
        </tr>
        <tr>
          <td align="middle">4</td>
          <td>right hand (weapon)</td>
        </tr>
        <tr>
          <td align="middle">5</td>
          <td>left hand (shield)</td>
        </tr>
        <tr>
          <td align="middle">6</td>
          <td>right finger (ring)</td>
        </tr>
        <tr>
          <td align="middle">7</td>
          <td>left finger (ring)</td>
        </tr>
        <tr>
          <td align="middle">8</td>
          <td>waist (belt)</td>
        </tr>
        <tr>
          <td align="middle">9</td>
          <td>feet (boots)</td>
        </tr>
        <tr>
          <td align="middle">10</td>
          <td>hands (gloves)</td>
        </tr>
        <tr>
          <td align="middle">11</td>
          <td>alternate right hand (Expansion Set only)</td>
        </tr>
        <tr>
          <td align="middle">12</td>
          <td>alternate left hand (Expansion Set only)</td>
        </tr>
      </tbody>
      </table>
    </td>
  </tr>
  <tr>
    <td align="middle">65</td>
    <td align="middle">4</td>
    <td>
      <p>Column number of the left corner of the item, counting from 0.
      Your inventory has ten columns (numbered 0-9), your stash has six, and the
      Horadric Cube has four.</p>
      <p><strong>Note:</strong> Your belt is considered (for the purposes of the
      item format) to have no rows, but either 4, 8, 12, or 16 columns. If
      you prefer, you can divide this field and use the 2 bits at position 67-68
      for the row (but only for belts).</p>
      <p><strong>Note 2:</strong> If the item is equipped, glued to a socket, or
      in transit, then this field appears to contain old data from the last time
      the item was stored. I.e., it may be non-zero, but the value is
      unused.</p></td>
  </tr>
  <tr>
    <td align="middle">69</td>
    <td align="middle">3</td>
    <td>
      <p>Row number of the top of the item, counting from 0. Your
      inventory has four rows (numbered 0-3), your stash has four in normal
      characters or eight in Expansion Set characters, and the Horadric Cube has
      four. (In the belt, this field is always zero.)</p>
      <p><strong>Note:</strong> If the item is equipped, tucked in your belt,
      glued to a socket, or in transit, then this field appears to contain old
      data from the last time the item was stored. I.e., it may be
      non-zero, but the value is unused.</p></td>
  </tr>
  <tr>
    <td align="middle">72</td>
    <td align="middle">1</td>
    <td><i>unknown</i></td>
  </tr>
  <tr>
    <td align="middle">73</td>
    <td align="middle">3</td>
    <td>
      <div><a name="73">Actually</a>, bit 74 seems to always be 0, but since bits
      73 and 75 are related I just lump them all together. If the item is
      neither equipped nor in your belt, this field tells where it is.
      Possible values are:</div>
      <table cellspacing="0" width="80%" align="center" border="1">
      <tbody>
        <tr>
          <td align="middle" width="20%">0</td>
          <td width="60%">not here <i>(check <a href="#58">bit field 58</a>)</i></td>
        </tr>
        <tr>
          <td align="middle">1</td>
          <td>inventory</td>
        </tr>
        <tr>
          <td align="middle">4</td>
          <td>Horadric Cube</td>
        </tr>
        <tr>
          <td align="middle">5</td>
          <td>stash</td>
        </tr>
      </tbody>
      </table>
      <div><u>If you find an item having any other value in this field, let me
      know what the value is and the item's location!</u></div></td>
  </tr>
  <tr>
    <td align="middle">76</td>
    <td align="middle">4 <tt>char</tt>s<br/>(8 bits ea.)</td>
    <td><a name="76">Item's type.</a> The type is 3 lower-case letters or
      numbers followed by a space; e.g., &quot;<tt>amu&#xA0;</tt>&quot; (Amulet) or &quot;<tt>2hs&#xA0;</tt>&quot;
      (Two-Handed Sword). I have started a list of item identifiers (not
      posted; sorry), but it is by no means complete; I'm sure I don't even have
      half of what's out there!<br/><strong>Warning:</strong> This field is
      <em>not</em> byte-aligned! It starts in the middle of byte 9 and
      runs to the middle of byte 13.</td>
  </tr>
  <tr>
    <td align="middle">108</td>
    <td align="middle">3</td>
    <td>The number of gems (or skulls or jewels) which have been glued to this
      item (if <a href="#27">socketed</a>).
      There will be this many additional item structures for the gems
      immediately following this item, in the order that the gems were inserted.</td>
  </tr>
</tbody>
</table>
<h2><a name="ear">Item Variant: Player Ears</a></h2>
<div><i>The following information was provided by Mike of Denmark.</i></div>
<p>If the item is a Player Ear, its structure is slightly different than the
Simple Items above. The last two fields in the Simple Item structure are
replaced by the following:</p>
<table width="100%" border="1">
<tbody>
  <tr>
    <th width="10%">Bit Position</th>
    <th width="10%">Size</th>
    <th>Contents</th>
  </tr>
  <tr>
    <td align="middle">76</td>
    <td align="middle">3</td>
    <td>Character class of the ear's former owner. The defined classes
      are:<br/>&#xA0;&#xA0;&#xA0;&#xA0; 0&#xA0;
      Amazon<br/>&#xA0;&#xA0;&#xA0;&#xA0; 1&#xA0;
      Sorceress<br/>&#xA0;&#xA0;&#xA0;&#xA0; 2&#xA0;
      Necromancer<br/>&#xA0;&#xA0;&#xA0;&#xA0; 3&#xA0;
      Paladin<br/>&#xA0;&#xA0;&#xA0;&#xA0; 4&#xA0;
      Barbarian<br/>&#xA0;&#xA0;&#xA0;&#xA0; 5&#xA0; Druid (Expansion character
      only)<br/>&#xA0;&#xA0;&#xA0;&#xA0; 6&#xA0; Assassin (Expansion character
      only)</td>
  </tr>
  <tr>
    <td align="middle">79</td>
    <td align="middle">7</td>
    <td>Character level of the ear's former owner.</td>
  </tr>
  <tr>
    <td align="middle">86</td>
    <td align="middle">7</td>
    <td>First character of the former owner's name.</td>
  </tr>
  <tr>
    <td align="middle">93</td>
    <td align="middle">7 &#xD7; <i>N</i>-1</td>
    <td>Second character of the former owner's name; Repeat until you get the
      whole name (15 characters maximum).</td>
  </tr>
  <tr>
    <td align="middle">86 + 7 &#xD7; <i>N</i></td>
    <td align="middle">7</td>
    <td>0&#xA0; (this indicates the end of the name)</td>
  </tr>
</tbody>
</table>
<p>Following the end of the name, the rest of the final byte will be padded with
0's if necessary, and the Player Ear structure ends there.</p>
<h2>Item Structure part 2: Extended Items</h2>
<p>By &quot;extended items&quot; I mean any items which are not <a href="#37">simple.</a>
Simple items are those which need no further information than that given
above &#x2014; such as gems, potions, and small quest items &#x2014; and their structure length
is fixed at 14 bytes. Everything else has an extended structure with a
possibly variable length set of bit fields. First, I'll describe the part
of the structure that appears to be the same for all extended items. From
that point on, there will be no more &quot;bit positions&quot;; only &quot;this field follows
that field, if it exists&quot;.</p>
<table width="100%" border="1">
<tbody>
  <tr>
    <th width="10%">Bit Position</th>
    <th width="10%">Size</th>
    <th>Contents</th>
  </tr>
  <tr>
    <td align="middle">111</td>
    <td align="middle">32</td>
    <td>Unique identifier. Diablo II randomly generates a value for this
      field in order to discourage cheaters from &quot;duping&quot; items.
      Supposedly, if it detects more than one extended item with the same unique
      Id, it will delete the duplicates. (It hasn't done that for me in
      single player mode, though.)</td>
  </tr>
  <tr>
    <td align="middle">143</td>
    <td align="middle">7</td>
    <td>
      <div>This appears to be the item's level; i.e., the level with which the
      item was created (or 'dropped'). The item level is based on the
      level of the monster who dropped it, the level of the area you're in if
      found in a chest, or, in rare cases, your characters level. The item
      level determines what modifiers are allowed on the item.</div>
      <div><i>Note: this is just a theory at this point, but it seems to hold
      for the items I've examined.</i></div></td>
  </tr>
  <tr>
    <td align="middle">150</td>
    <td align="middle">4</td>
    <td>
      <div>Item quality. This field can be one of the following values,
      which determines the quality-specific bit fields that follow:</div>
      <table cellspacing="0" width="80%" align="center" border="1">
      <tbody>
        <tr>
          <td align="middle" width="20%">1</td>
          <td width="60%"><a href="#low_quality">low quality</a></td>
        </tr>
        <tr>
          <td align="middle">2</td>
          <td><a href="#normal_data">normal</a></td>
        </tr>
        <tr>
          <td align="middle">3</td>
          <td><a href="#high_quality">high quality</a></td>
        </tr>
        <tr>
          <td align="middle">4</td>
          <td><a href="#magic_data">magically enhanced</a></td>
        </tr>
        <tr>
          <td align="middle">5</td>
          <td><a href="#set_data">part of a set</a></td>
        </tr>
        <tr>
          <td align="middle">6</td>
          <td><a href="#rare_data">rare</a></td>
        </tr>
        <tr>
          <td align="middle">7</td>
          <td><a href="#unique_data">unique</a></td>
        </tr>
        <tr>
          <td align="middle">8</td>
          <td><a href="#crafted_data">crafted</a></td>
        </tr>
      </tbody>
      </table>
      <div><i>Thanks go to Guillaume Courtin of France for finding the value of
      crafted items.</i></div></td>
  </tr>
</tbody>
</table>
<h2 align="center">WARNING: DATA BELOW THIS POINT MAY CONTAIN ERRORS</h2>
<h3><a name="ring_data">Ring Data</a></h3>
<p>After the above data, if the item is a ring, amulet, jewel, or charm, then it
has a 1 bit followed by three more bits. All other items (that I've seen)
have just a single 0 bit.</p>
<table width="100%" border="1">
<tbody>
  <tr>
    <th width="20%">Size</th>
    <th colspan="2">Contents</th>
  </tr>
  <tr>
    <td align="middle">1</td>
    <td colspan="2">If this bit is set, the item has one of multiple pictures
      associated with it; the next field determines which picture a particular
      item uses. If this bit is 0, the next field is absent. The
      picture field is used for rings, amulets, jewels, and charms.</td>
  </tr>
  <tr>
    <td align="middle">3</td>
    <td>Picture. <i>Optional; only present if the previous bit is 1.</i>
      This field chooses the particular graphic used to display the ring.</td>
    <td width="179"><img height="75" src="/web/20161225040510im_/http://www.coreyh.org/diablo-2-files/documentation/images/Ring_of_the_Leech.jpg" width="179"/></td>
  </tr>
</tbody>
</table>
<p>From this point on, my information is very iffy.</p>
<h3><a name="unknown_11bit_data"><i>Unknown Field</i></a></h3>
<table width="100%" border="1">
<tbody>
  <tr>
    <th width="20%">Size</th>
    <th>Contents</th>
  </tr>
  <tr>
    <td align="middle">1</td>
    <td>This bit apparently is set for certain class-specific Expansion Set
      items. It indicates the presence of the next 11-bit field. If
      this bit is 0, the next field is absent.</td>
  </tr>
  <tr>
    <td align="middle">11</td>
    <td>
      <div><i>Credit for the discovery of this field's meaning goes entirely to
      Guillaume Courtin of France. Thanks!</i></div>
      <div>This field indicates magic properties which are inherent in certain
      class-specific items. A given class-specific item will (almost)
      always start with the same set of properties, even if its quality is
      &quot;normal&quot;. Other quality ratings may add more properties to the
      standard set. It appears that items which will have this field
      are:</div>
      <ul>
        <li>Amazon-only bows, spears, and javelins</li>
        <li>Voodoo heads (Necromancer-only shields)</li>
        <li>Paladin-only shields</li>
        <li>Orbs (Sorceress-Only wands)</li></ul></td>
  </tr>
</tbody>
</table>
<h3><a name="low_quality">Low Quality Item Data</a></h3>
<p>If the item is one of low quality, it has 3 more bits that give the quality
details:</p>
<table width="100%" border="1">
<tbody>
  <tr>
    <th width="20%">Size</th>
    <th colspan="2">Contents</th>
  </tr>
  <tr>
    <td align="middle">3</td>
    <td>
      <div>Quality:</div>
      <table cellspacing="0" width="80%" align="center" border="1">
      <tbody>
        <tr>
          <td align="middle" width="20%">0</td>
          <td width="60%">Crude</td>
        </tr>
        <tr>
          <td align="middle">1</td>
          <td>Cracked</td>
        </tr>
        <tr>
          <td align="middle">2</td>
          <td>Damaged</td>
        </tr>
        <tr>
          <td align="middle">3</td>
          <td>Low Quality</td>
        </tr>
      </tbody>
      </table>
      <div><i>I haven't recorded any instances of other values, but that doesn't
      mean there won't be any. Also, I'm certain the value has something
      to do with mods on an item's inherent (non-recorded) properties, such as
      weapon damage, but I haven't figured out yet what the correlation is.</i></div></td>
    <td width="173"><img height="121" src="/web/20161225040510im_/http://www.coreyh.org/diablo-2-files/documentation/images/Crude_Heavy_Boots.jpg" width="173"/></td>
  </tr>
</tbody>
</table>
<h3><a name="normal_data">Normal Item Data</a></h3>
<p>Normal items have no extra quality data.</p>
<h3><a name="low_quality">High Quality ("Superior") Item Data</a></h3>
<p>If the item is one of high quality, it has 3 additional bits.</p>
<table width="100%" border="1">
<tbody>
  <tr>
    <th width="20%">Size</th>
    <th>Contents</th>
  </tr>
  <tr>
    <td align="middle">3</td>
    <td><i>unknown. I'm certain the value has something to do with mods
      on an item's inherent (non-recorded) properties, such as weapon damage,
      but I haven't figured out yet what the correlation is.</i></td>
  </tr>
</tbody>
</table>
<h3><a name="magic_data">Magically Enhanced Item Data</a></h3>
<p><img src="/web/20161225040510im_/http://www.coreyh.org/diablo-2-files/documentation/images/Sturdy_Spiked_Shield_of_Spikes.jpg" align="right"/>
Magically enhanced items have two 11-bit fields representing the item's prefix
and suffix. Either one (but not both) may be omitted. The prefix and
suffix each are used in choosing the <a href="#enhancements">magical
enhancements</a> for an item (although the enhancements are modifiable), and can
also increase the minimum level required to use them item and affect the item's
color.</p><img src="/web/20161225040510im_/http://www.coreyh.org/diablo-2-files/documentation/images/Mesh_Belt_of_the_Mammoth.jpg" align="left"/>
<br clear="both"/>
<table width="100%" border="1">
<tbody>
  <tr>
    <th width="20%">Size</th>
    <th>Contents</th>
  </tr>
  <tr>
    <td align="middle">11</td>
    <td>Item prefix (i.e., &quot;Gold&quot; or &quot;Tangerine&quot;). I've started a <a href="Magic_Names.html#prefix">list
      of prefix identifiers</a>, but it is very sparse at this time. If
      this field is 0, the item has no prefix.</td>
  </tr>
  <tr>
    <td align="middle">11</td>
    <td>Item suffix (i.e., &quot;of Greed&quot; or &quot;of Life&quot;). I've started a <a href="Magic_Names.html#suffix">list
      of suffix identifiers</a>, but it is very sparse at this time. If
      this field is 0, the item has no suffix.</td>
  </tr>
</tbody>
</table>
<h3><a name="set_data">Set Item Data</a></h3>
<p></p>Set items have a 12-bit field containing the ID of the set.
<em>(Not the set member, but the whole set.)</em> The set member is
identified by cross-referencing the <a href="#76">item
type</a> with the set Id. Also note that set items have <a href="#set_extended_data">an
extra field</a> following the <a href="#specific">item-specific data</a>.
<p><!-- @ --></p>
<table width="100%" border="1">
<tbody>
  <tr>
    <th width="20%">Size</th>
    <th colspan="2">Contents</th>
  </tr>
  <tr>
    <td align="middle">12</td>
    <td>
      <div>Set identifier; i.e., all items which are part of the set will have
      the same value in this field. Since I've only identified a few set
      items, I'll give their ID's here:</div>
      <table cellspacing="0" width="80%" align="center" border="1">
      <tbody>
        <tr>
          <td align="middle" width="20%">2</td>
          <td width="60%"><span color="#004000">Cleglaw's Brace</span></td>
        </tr>
        <tr>
          <td align="middle">3</td>
          <td><span color="#004000">Iratha's Finery</span></td>
        </tr>
        <tr>
          <td align="middle">4</td>
          <td><span color="#004000">Isenhart's Armory</span></td>
        </tr>
        <tr>
          <td align="middle">6</td>
          <td><span color="#004000">Milabrega's Regalia</span></td>
        </tr>
        <tr>
          <td align="middle">7</td>
          <td><span color="#004000">Cathan's Traps</span></td>
        </tr>
        <tr>
          <td align="middle">11</td>
          <td><span color="#004000">Berserker's Arsenal</span></td>
        </tr>
        <tr>
          <td align="middle">12</td>
          <td><span color="#004000">Death's Disguise</span></td>
        </tr>
        <tr>
          <td align="middle">13</td>
          <td><span color="#004000">Angelic Raiment</span></td>
        </tr>
      </tbody>
      </table></td>
    <td width="245"><img height="250" src="/web/20161225040510im_/http://www.coreyh.org/diablo-2-files/documentation/images/Deaths_Hand_Leather_Gloves.jpg" width="245"/></td>
  </tr>
</tbody>
</table>
<h3><a name="rare_data">Rare Item Data</a></h3>
<p><img height="294" src="/web/20161225040510im_/http://www.coreyh.org/diablo-2-files/documentation/images/Loath_Song_Battle_Axe.jpg" width="253" align="right"/> This is by far the worst beast to decode. Rare items have a
variable number of bits before we get to the item contents, and this number can
vary anywhere from 55 to 88!</p>
<p><img height="156" src="/web/20161225040510im_/http://www.coreyh.org/diablo-2-files/documentation/images/Eagle_Mark_Amulet.jpg" width="331" align="left"/> <i>Update 3/14/2002:</i> <strong>EUREKA!!</strong> I've
finally figured out the variable fields!; See the table below.<br clear="both"/></p>
<table width="100%" border="1">
<tbody>
  <tr>
    <th width="20%">Size</th>
    <th>Contents</th>
  </tr>
  <tr>
    <td align="middle">8</td>
    <td>This is the Id for the <a href="Magic_Names.html#rare_first_name">first
      word of the item's name</a> (i.e., &quot;Stone&quot; or &quot;Doom&quot;).</td>
    </tr>
  <tr>
    <td align="middle">8</td>
    <td>This is the ID for the <a href="Magic_Names.html#rare_second_name">second
      word of the item's name</a> (i.e., &quot;Finger&quot; or &quot;Shroud&quot;).</td>
  </tr>
  <tr>
    <td align="middle">1</td>
    <td>If this field is 1, the next 11-bit field is present. If 0, the
      next field is absent.</td>
  </tr>
  <tr>
    <td align="middle">11</td>
    <td>First <a href="Magic_Names.html#prefix">magic
      prefix</a> <i>(optional)</i>. Although this &quot;prefix&quot; isn't actually
      shown in the item name, it is used in determining the magical properties,
      required level, coloring, and other attributes of the rare item.</td>
  </tr>
  <tr>
    <td align="middle">1</td>
    <td>If this field is 1, the next 11-bit field is present. If 0, the
      next field is absent.</td>
  </tr>
  <tr>
    <td align="middle">11</td>
    <td>First <a href="Magic_Names.html#suffix">magic
      suffix</a> <i>(optional)</i>. Although this &quot;suffix&quot; isn't actually
      shown in the item name, it is used in determining the magical properties,
      required level, coloring, and other attributes of the rare item.</td>
  </tr>
  <tr>
    <td align="middle">1</td>
    <td>If this field is 1, the next 11-bit field is present. If 0, the
      next field is absent.</td>
  </tr>
  <tr>
    <td align="middle">11</td>
    <td>Second magic prefix <i>(optional)</i></td>
  </tr>
  <tr>
    <td align="middle">1</td>
    <td>If this field is 1, the next 11-bit field is present. If 0, the
      next field is absent.</td>
  </tr>
  <tr>
    <td align="middle">11</td>
    <td>Second magic suffix <i>(optional)</i></td>
  </tr>
  <tr>
    <td align="middle">1</td>
    <td>If this field is 1, the next 11-bit field is present. If 0, the
      next field is absent.</td>
  </tr>
  <tr>
    <td align="middle">11</td>
    <td>Third magic prefix <i>(optional)</i></td>
  </tr>
  <tr>
    <td align="middle">1</td>
    <td>If this field is 1, the next 11-bit field is present. If 0, the next field is absent.</td>
  </tr>
  <tr>
    <td align="middle">11</td>
    <td>Third magic suffix <i>(optional)</i></td>
  </tr>
</tbody>
</table>
<h3><a name="unique_data">Unique Item Data</a></h3>
<p>Unique items have an additional 12 bit field, which in <em>most</em> cases is
the unique item ID. The few exceptions are certain quest items (e.g., the
Horadric Malus).</p>
<table width="100%" border="1">
<tbody>
  <tr>
    <th width="20%">Size</th>
    <th colspan="2">Contents</th>
  </tr>
  <tr>
    <td align="middle">12</td>
    <td>
      <div>Item identifier. Since I've only identified a few unique items,
      I'll give their ID's here:</div>
      <table cellspacing="0" width="80%" align="center" border="1">
      <tbody>
        <tr>
          <td align="middle" width="20%">13</td>
          <td width="60%"><span color="#8b6914">Ume's Lament</span> Grim Wand</td>
        </tr>
        <tr>
          <td align="middle">31</td>
          <td><span color="#8b6914">Hellplague</span> Long Sword</td>
        </tr>
        <tr>
          <td align="middle">75</td>
          <td><span color="#8b6914">Wormskull</span> Bone Helm</td>
        </tr>
        <tr>
          <td align="middle">77</td>
          <td><span color="#8b6914">Undead Crown</span> Crown <i>(no, that is not a typo!)</i></td>
        </tr>
        <tr>
          <td align="middle">91</td>
          <td><span color="#8b6914">Goldskin</span> Full Plate Mail</td>
        </tr>
        <tr>
          <td align="middle">120</td>
          <td><span color="#8b6914">Nagelring</span> Ring <i>(not a typo either; I checked)</i></td>
        </tr>
        <tr>
          <td align="middle">123</td>
          <td>Amulet <span color="#8b6914">of the Viper</span></td>
        </tr>
        <tr>
          <td align="middle">125</td>
          <td><span color="#8b6914">Horadric</span> Staff</td>
        </tr>
        <tr>
          <td align="middle">126</td>
          <td><span color="#8b6914">Hell Forge</span> Hammer</td>
        </tr>
        <tr>
          <td align="middle">4095<br/>(0xFFF)</td>
          <td><span color="#8b6914"><i>(other; probably a quest
          item)</i></span></td>
        </tr>
      </tbody>
      </table>
    </td>
    <td width="332"><img height="310" src="/web/20161225040510im_/http://www.coreyh.org/diablo-2-files/documentation/images/Hellplague.jpg" width="332"/></td>
  </tr>
</tbody>
</table>
<h3><a name="crafted_data">Crafted Item Data</a></h3>
<p>Crafted items appear to be coded exactly like rare items, having a rare name
(two parts) and six optional prefixes / suffixes.</p>
<table width="100%" border="1">
<tbody>
  <tr>
    <th width="20%">Size</th>
    <th>Contents</th>
  </tr>
  <tr>
    <td align="middle">8</td>
    <td>This is the Id for the <a href="Magic_Names.html#rare_first_name">first
      word of the item's name</a> (i.e., &quot;Stone&quot; or &quot;Doom&quot;).</td>
  </tr>
  <tr>
    <td align="middle">8</td>
    <td>This is the Id for the <a href="Magic_Names.html#rare_second_name">second
      word of the item's name</a> (i.e., &quot;Finger&quot; or &quot;Shroud&quot;).</td>
  </tr>
  <tr>
    <td align="middle">1</td>
    <td>If this field is 1, the next 11-bit field is present. If 0, the
      next field is absent.</td>
  </tr>
  <tr>
    <td align="middle">11</td>
    <td>First <a href="Magic_Names.html#prefix">magic
      prefix</a> <i>(optional)</i>. Although this &quot;prefix&quot; isn't actually
      shown in the item name, it is used in determining the magical properties,
      required level, coloring, and other attributes of the crafted item.</td>
  </tr>
  <tr>
    <td align="middle">1</td>
    <td>If this field is 1, the next 11-bit field is present. If 0, the
      next field is absent.</td>
  </tr>
  <tr>
    <td align="middle">11</td>
    <td>First <a href="Magic_Names.html#suffix">magic
      suffix</a> <i>(optional)</i>. Although this &quot;suffix&quot; isn't actually
      shown in the item name, it is used in determining the magical properties,
      required level, coloring, and other attributes of the crafted item.</td>
  </tr>
  <tr>
    <td align="middle">1</td>
    <td>If this field is 1, the next 11-bit field is present. If 0, the
      next field is absent.</td>
  </tr>
  <tr>
    <td align="middle">11</td>
    <td>Second magic prefix <i>(optional)</i></td>
  </tr>
  <tr>
    <td align="middle">1</td>
    <td>If this field is 1, the next 11-bit field is present. If 0, the
      next field is absent.</td>
  </tr>
  <tr>
    <td align="middle">11</td>
    <td>Second magic suffix <i>(optional)</i></td>
  </tr>
  <tr>
    <td align="middle">1</td>
    <td>If this field is 1, the next 11-bit field is present. If 0, the
      next field is absent.</td>
  </tr>
  <tr>
    <td align="middle">11</td>
    <td>Third magic prefix <i>(optional)</i></td>
  </tr>
  <tr>
    <td align="middle">1</td>
    <td>If this field is 1, the next 11-bit field is present. If 0, the
      next field is absent.</td>
  </tr>
  <tr>
    <td align="middle">11</td>
    <td>Third magic suffix <i>(optional)</i></td>
  </tr>
</tbody>
</table>
<h3><a name="runeword">Rune Word</a></h3>
<p>If the item has a rune word (indicated by <a href="#42">bit
42</a> being set), there is an additional field at this point.</p>
<table width="100%" border="1">
<tbody>
  <tr>
    <th width="20%">Size</th>
    <th>Contents</th>
  </tr>
  <tr>
    <td align="middle">12</td>
    <td>This <em>appears</em> to be an index to the rune word, although I
      can't say what the index is based on. The first rune word,
      &quot;Ancient's Pledge&quot;, has a value of 27. The next rune word, &quot;Black&quot;,
      has a value of 32. etc.</td>
  </tr>
  <tr>
    <td align="middle">4</td>
    <td><i>Unknown; the value is 5 on all items I've looked at.</i></td>
  </tr>
</tbody>
</table>
<h3><a name="personalized">Personalization</a></h3>
<p>The following segment is present if and only if the item is personalized
(i.e., <a href="#40">bit
40</a> is set). Only armor and weapons (except for quest items) can be
personalized.</p>
<table width="100%" border="1">
<tbody>
  <tr>
    <th width="20%">Size</th>
    <th>Contents</th>
  </tr>
  <tr>
    <td align="middle">7</td>
    <td>First character of the owner's name (just plain ASCII!)</td>
  </tr>
  <tr>
    <td align="middle">7</td>
    <td>Second character of the owner's name</td>
  </tr>
  <tr>
    <td align="middle">7 &#xD7; <i>N</i>-2</td>
    <td>Repeat until you get the whole name (15 characters maximum)</td>
  </tr>
  <tr>
    <td align="middle">7</td>
    <td>0&#xA0; (this indicates the end of the name)</td>
  </tr>
</tbody>
</table>
<h3><a name="unknown_11bit_data"><i>Unknown Field</i></a></h3>
<p>All items have this field between the personalization (if it exists) and the
item-specific data:</p>
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<tbody>
  <tr>
    <th width="20%">Size</th>
    <th>Contents</th>
  </tr>
  <tr>
    <td align="middle">1</td>
    <td><i>unknown; this usually is 0, but is 1 on a Tome of Identify.
      (It's still 0 on a Tome of Townportal.)</i></td>
  </tr>
</tbody>
</table>
<h2><a name="specific">Item Structure part 3: Item-Specific Data</a></h2>
<p>The presence of the following fields depends on the item type. Fields
which are present will be stored in the order shown. Unfortunately there
is no means of telling which fields are present from the item data itself; you
need to look up the <a href="#76">item
type</a> in a table to figure out whether it is a weapon, armor, or stack, and
read the fields accordingly.</p>
<h3>Armor: Defense Rating</h3>
<table width="100%" border="1">
<tbody>
  <tr>
    <th width="20%">Size</th>
    <th>Contents</th>
  </tr>
  <tr>
    <td align="middle">10</td>
    <td>Defense value +10. i.e., a defense rating of 23 would be
      stored in this field as 33; thus the maximum defense value you can store
      is 1013 (although I haven't tried it). Note that this is the base
      defense rating, before applying any magical enhancements (i.e., the number
      shown in white).</td>
  </tr>
</tbody>
</table>
<h3>Armor and Weapons: Durability</h3>
<p>Even though stacked weapons don't show any durability rating in the game,
they still have two 8-bit fields in the same spot. This includes bombs
(exploding and gas potions). The values in such cases are very small, so
I'm not sure what they mean.</p>
<table width="100%" border="1">
<tbody>
  <tr>
    <th width="20%">Size</th>
    <th>Contents</th>
  </tr>
  <tr>
    <td align="middle">8</td>
    <td>Maximum Durability. Note that this is the base durability,
      before applying any magical enhancements (i.e., the number shown in
      white).<br/><i>Note: </i>I've found an indestructable item, and it appears
      that in such a case the maximum durability field is zero!</td>
  </tr>
  <tr>
    <td align="middle">8</td>
    <td>Current Durability. This may be greater than the maximum
      durability if the item is magically enhanced.<br/><i>Note: </i>I've found
      an indestructable item, and it appears that in such a case the current
      durability field is missing!</td>
  </tr>
</tbody>
</table>
<h3><a name="sockets">Armor and (non-stacked) Weapons: Sockets</a></h3>
<p>The following field is present if and only if the item is socketed (i.e., <a href="#27">bit
27</a> is set).</p>
<table width="100%" border="1">
<tbody>
  <tr>
    <th width="20%">Size</th>
    <th colspan="2">Contents</th>
  </tr>
  <tr>
    <td align="middle">4</td>
    <td>Number of sockets<br/><i>Note that even though this field is 4 bits
      wide, each item type has a built-in upper limit to the total number of
      sockets. This limit is built into the game. The most I've ever
      seen is 6 for, e.g., a gothic axe.</i></td>
    <td width="179"><img height="137" src="/web/20161225040510im_/http://www.coreyh.org/diablo-2-files/documentation/images/Socketed_Mask.jpg" width="179"/></td>
  </tr>
</tbody>
</table>
<h3>Tomes:</h3>
<p>Tomes have an extra 5 bits inserted at this point. I have no idea what
purpose they serve. It looks like the value is 0 on all of my tomes.</p>
<table width="100%" border="1">
<tbody>
  <tr>
    <th width="20%">Size</th>
    <th>Contents</th>
  </tr>
  <tr>
    <td align="middle">5</td>
    <td><i>unknown</i></td>
  </tr>
</tbody>
</table>
<h3>Stacked Weapons, Quivers, Keys, and Tomes: Quantity</h3>
<table width="100%" border="1">
<tbody>
  <tr>
    <th width="20%">Size</th>
    <th>Contents</th>
  </tr>
  <tr>
    <td align="middle">9</td>
    <td>Quantity</td>
  </tr>
</tbody>
</table>
<h2><a name="enhancements">Item Structure part 3: Magical Enhancements</a></h2>
<h3>Item Structure part 2<sup>bis</sup>: <a name="set_extended_data">Set Item Data
Revisited</a></h3>
<p>Items which are part of a set have an additional 5 bits following the
item-specific data.</p>
<table width="100%" border="1">
<tbody>
  <tr>
    <th width="20%">Size</th>
    <th>Contents</th>
  </tr>
  <tr>
    <td align="middle">5</td>
    <td>This appears to be an indicator of how many lists of magic properties
      follows. The first list are the properties the item has if you do
      not have any other members of the set. Following lists are applied
      once you equip other items in the set. The value is 1 if there are
      two (total) property lists, or 3 if there are three property lists.</td>
  </tr>
</tbody>
</table>
<p>Following the item-specific data are a variable number of variable length bit
fields describing any magical enhancements placed on the item. Each
property begins with a 9-bit identifier. An identifier of <tt>0x1FF</tt>
(all 1's) indicates the end of the property list ... except in the event the
item belongs to a set, in which case there will be another one or two groups of
magical properties following, depending on whether the set item data (above) is
1 or 3, respectively. Also, if an item has been given a <a href="#42">Rune
Word</a>, it appears that the Rune Word's properties begin with a <tt>0x1FF</tt>
identifier (presumably to set them apart from the item's normal properties...
but I need to examine more items to be certain.)</p>
<p>Because the number of bits (and fields) after the 9-bit identifier varies, I
do not give a field width here. Instead, check my <a href="Magic_Properties.html">table
of magic properties</a> for field sizes. I'm sure it's not complete, but
it does have most of the common properties.</p>
<p>Following the last 9-bit value of 0x1FF, the rest of the final byte will be
padded with 0's if necessary, and the item structure ends there. For
example, if the item had 341 bits of data, the last (43<sup>rd</sup>) byte will
be 0x1F. If the item had 248 bits of data, the last (31<sup>st</sup>) byte
will be 0xFF.</p>
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</html>