Configure entities through KubeJS. The mod records nearby players when a configured entity spawns and scales its health for that group. On death, each recorded player receives a personal copy of the normal item drops. Shared-item exceptions, persistent ownership and standard hopper protection are supported. Experience is not duplicated. Players joining the fight later are not added to the recorded group.
Example in kubejs/server_scripts/boss_scaling.js:
BossScalingSystem.addEntityConfig('minecraft:zombie', [], 1.0)
The second argument lists items that stay shared. The third argument adds that fraction of base health for each player after the first. Players are recorded within a 40-block sphere; spectators are excluded. Configuration is required: no entities are registered automatically.
This is a mod, maintained for DepthWard modpack.
You can use this mod in any project you like, as long as it stays within the scope of the Curse Forge platform.

