> For the complete documentation index, see [llms.txt](https://axiomemu.gitbook.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://axiomemu.gitbook.io/docs/data/item.md).

# Item Configuration

Item configuration controls drop rates, options, and special effects

The item configuration system controls how items are generated when they drop from monsters, are created through chaos mixes, or given through events.

See also: [Data overview](/docs/data/data.md) for sibling sections, and [Shop System](/docs/data/shop.md) for NPC shop inventories that reference these item definitions.

## Configuration Files

### Core Item Database

| File                                                              | Purpose                                                        |
| ----------------------------------------------------------------- | -------------------------------------------------------------- |
| [Item](/docs/data/item/item.md)                                   | Master item database (stats, requirements, classes)            |
| [ItemDrop](/docs/data/item/itemdrop.md)                           | Specific monster drop rules with full option control           |
| [ItemOptionRate](/docs/data/item/itemoptionrate.md)               | Probability tables for item options (level, skill, luck, etc.) |
| [ItemOption](/docs/data/item/itemoption.md)                       | Stat bonuses applied based on item options                     |
| [ExcellentOptionRate](/docs/data/item/excellentoptionrate.md)     | Which excellent bits apply to which item ranges                |
| [OptionIndex Reference](/docs/data/item/optionindex-reference.md) | Complete list of 75 stat effect types                          |

### Set Items

| File                                              | Purpose                          |
| ------------------------------------------------- | -------------------------------- |
| [SetItemType](/docs/data/item/setitemtype.md)     | Which items belong to which sets |
| [SetItemOption](/docs/data/item/setitemoption.md) | Set piece and full set bonuses   |

### Socket Items

| File                                                    | Purpose                                 |
| ------------------------------------------------------- | --------------------------------------- |
| [SocketItemType](/docs/data/item/socketitemtype.md)     | Which items can have sockets            |
| [SocketItemOption](/docs/data/item/socketitemoption.md) | Socket seed options and element bonuses |

### Enhancement Systems

| File                                                            | Purpose                                |
| --------------------------------------------------------------- | -------------------------------------- |
| [380ItemType](/docs/data/item/380itemtype.md)                   | Which items can have 380 enhancement   |
| [380ItemOption](/docs/data/item/380itemoption.md)               | 380 PvP option definitions             |
| [JewelOfHarmonyType](/docs/data/item/jewelofharmonytype.md)     | Item level requirements for JoH        |
| [JewelOfHarmonyOption](/docs/data/item/jewelofharmonyoption.md) | JoH bonuses for weapons, staves, armor |
| [LuckyItem](/docs/data/item/luckyitem.md)                       | Lucky item definitions and time decay  |

### Item Utility

| File                                      | Purpose                              |
| ----------------------------------------- | ------------------------------------ |
| [ItemStack](/docs/data/item/itemstack.md) | Stack sizes and transformation rules |
| [ItemValue](/docs/data/item/itemvalue.md) | Custom prices and currency types     |
| [ItemMove](/docs/data/item/itemmove.md)   | Trade/drop/sell/vault restrictions   |

## How Item Generation Works

When an item is created, the server:

1. **Determines the base item** - From drop tables or mix recipes
2. **Rolls for options** - Uses ItemOptionRate to determine level, skill, luck, etc.
3. **Applies option effects** - Uses ItemOption to set stat bonuses

```
Item Drop → ItemOptionRate (what options?) → ItemOption (what stats?)
```

## Key Concepts

### Option Rate Indices

Both ItemOptionRate and ItemOption use index values to categorize different drop or generation sources. Lucky items pull whichever indices are written into Option0-6 of the LuckyItem entry, so the index assignments below are a convention used by the shipping data files rather than hard-coded behaviour:

| Index | Convention             | Example                      |
| ----- | ---------------------- | ---------------------------- |
| 0     | Common monster drops   | Regular gameplay             |
| 1     | Excellent item drops   | Rare monster drops           |
| 2     | Set item drops         | Ancient items                |
| 3     | Chaos mix results      | Chaos Machine                |
| 9     | NPC merchant purchases | Moss Merchant - TODO: verify |
| 10    | Lucky item rolls       | Lucky Ticket chaos mix       |
| 11+   | Event item bags        | Specific event drops         |

### Rate Scale

All rates use a scale of **10000 = 100%**:

| Rate Value | Percentage |
| ---------- | ---------- |
| 10000      | 100%       |
| 7000       | 70%        |
| 500        | 5%         |
| 100        | 1%         |
| 10         | 0.1%       |

{% hint style="info" %}
Rates are **weighted random selection**, not cumulative. If you have Rate0=7000, Rate1=2000, Rate2=1000, the system picks one outcome with those relative weights.
{% endhint %}

## Common Customizations

### Making Items Rarer

Increase Rate0 (level 0) values and decrease higher level rates in ItemOptionRate.

### Creating Powerful Event Rewards

Use high-index EventItemBag entries (11+) with guaranteed high levels and options.

### Balancing Excellent Items

Adjust the ExcOptions section to control how many excellent options spawn on items.