I am getting this message in the editor
[code]Design: Could not find levelgroup for object MyRing
Probably because there's not match with for ItemGroup Rings and Level 6[/code]
This is showing for almost every item stats that I create by copying from existing stats. I have tried different ActPart values but the message shows up for each value. The items, however work as expected and I have noticed that my equipped items disappear randomly during level up. Not sure if those messages have anything to do with that.

Can someone help me out here?

Levelgroups are referring to DOS2's item progression system. When items are created via stats (like from treasure tables), they naturally look to item progression to figure out what rarity to spawn in as for what levels.

So the stats you need are ItemProgressionVisuals, and ItemProgressionNames. ItemProgressionVisuals links ItemGroup to root templates and a namegroup - ItemProgressionNames defines your namegroups, which determines the item's name and description.

For example, say you have a sword:


The "ItemGroup" is "WPN_Fighter_Sword_1H_Lizards". We take that and create a new ItemProgressionVisuals entry:



Since our levelgroup is 0,0,"All", this item will always spawn at all levels, and all rarities. The rootgroup value is the GUIDSTRING of a sword root template to use for this item, and "LizardsCommon" is an ItemColor to use.

The namegroup, "Lizard's Sword", is defined in ItemProgressionNames:


namecool is used when the item spawns at a higher rarity.

The second value (omitted with "") is the description:



If the description is left blank (""), the item will use the root template's description.
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Note that defining rarities for your itemgroups to spawn at will require more entries - One for each level range to be exact. Here's some examples from Shared:


These entries keep going for each rarity and level range, up to Epic and level 19.

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One other thing to think about is that you can use a pre-existing ItemGroup to piggyback your item onto existing ItemProgression entries.

For instance, the ItemGroup "Bows" has level and rarity entries all the way up to level 19, so simply setting your weapon stat's ItemGroup to "Bows" is enough to include it in that range of levels and rarities.

This is a great guide LaughingLeader, you should add it to the wiki.

Thanks for the guide LaughingLeader. This is a valuable insight into the how the progression should be defined for custom items in the game.

Funny you should mention it, I wrote up an initial draft for an Item Progression guide today: Item Progression (Larian Wiki)

You're very welcome. Hopefully that sheds some light on what to do to get new items working in the game.

Good guide!
Something did catch my eye: I notice you use text-only examples rather than refer to how the data is presented in the Glasses stats editor. Is that how you usually edit them, through a text editor?

Yes. I used to use the stats editor for the first few months, but it turned out to be way faster/more efficient to do it purely in Notepad++, since I could have Shared/Origins on the right for faster copying, and control the final result a bit more (I had some issues with getting stat subtables and inherited skills to generate correctly).

I tend to have StatObjectDefinitions.sod and Enumerations.xml open in another tab, for reference to what the property and enum values are, to fill in that gap for what I'm missing by not using the stats editor.

Additionally, it's usually easier to share examples via the generate stats, since you have a vertical advantage that way.

With that said, I'm all for the stats being redone in the stats editor style, if that'll be more appropriate. That slipped my mind when writing the guide, haha.