GitLab

MM Version 5.3.2
Build: 18ded834
Non Premium
git-paper-43 | MC: 1.20.1

Use the following mobs:

SlimeHitBox:
  Type: SLIME 
  Options:
    NoAI: true
    PassthroughDamage: true
  Health: 9000000

TestDragon:
  Type: ALLAY
  Disguise: ENDER_DRAGON
  Display: "&7[Lv40] &cDragon"
  Skills:
  - summon{type=SlimeHitBox;amount=1;radius=1} @self ~onSpawn
  AITargetSelectors:
  - clear
  AIGoalSelectors:
  - clear
  - patrol -669,42,-234;-692,23,-252;-707,36,-290;-675,54,-315;-650,29,-296;-670,21,-276;-653,30,-260
  Options:
    NoDamageTicks: 1
    Collidable: false
  Health: 9000000

When hit with a power 10k bow, the parent (Allay/Dragon) does not recieve the damage.

Here is a pic with damage reports: