D2 Affix

Elite types are defined as data templates in data/d2affix/elite_types JSON files and registered with an ID. Each type can carry a tier, a set of affixes and an optional list of applicable tags or entities, so a type spawns only on matching monsters. Types with neither restriction can apply to any eligible mob. Child types extend a parent and inherit its fields, overriding only what they change. Kill flags prevent a type from triggering repeatedly on the same monster.

The mod covers common base tiers, champion and minion types, unique and super unique templates, and a set of undead bosses with fixed equipment. Affix numbers scale with the difficulty tier, and a difficulty can be set manually with the d2affix command. Elite state is saved in the overworld through SavedData, so monsters keep their affixes across sessions. The system needs both the client and the server to run, and it is open source under the MIT License.