Is there any error in my bonus configuration?

I want to create an artifact that can upgrade level 7 troops into level 8 troops, and before I start, I added a bonus to test if it works. However I received an error in the console:

Unknown identifier!
Request for .hellBaron from mod level-upgrader

I have already installed the WoG mod and I marked it as a dependency in the mod configuration file, and here is my bonus configuration:

"upgradeArchDevils": {
  "type" : "SPECIAL_UPGRADE",
  "subtype": "core:archDevil",
  "addInfo": "wake-of-gods.level8units:hellBaron"
}

I cant figure out whats wrong because theres no example of this type of bonus in the doc. So is there any error in my bonus configuration?

Second code works, right?

Do you mean the “subtype” entry? That wasnt mentioned in the log.

vcmi/docs/modders/Bonus/Bonus_Types.md at develop · vcmi/vcmi (github.com)

There is actual description (for 1.4)

That’s where I found the bonus.

Oh Ive found out the correct format. It should be creature.archDevil and creature.hellBaron.

Try something easier

"upgradeArchDevils": {
  "type" : "SPECIAL_UPGRADE",
  "subtype": "archDevil",
  "addInfo": "hellBaron" }

Of course you have to write wake-of-gods.level8units dependency in mod.json

I think for addInfo we sill require entity type, so should be like this:

"upgradeArchDevils": {
  "type" : "SPECIAL_UPGRADE",
  "subtype": "archDevil",
  "addInfo": "creature.hellBaron"
}

(for subtype both creature.archDevil and simple archDevil should work though)

Tried. The prefix creature. is needed in the addInfo section. Anyway, the problem has been solved. Thanks.