The Wither effect should not harm the Wither Skeleton.
Because of Wither Skeleton is already a the Skeleton of withered.
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is duplicated by 1
relates to 2
Comments 3
This can be fixed by copying the Spider poison effect (where a spider is immume to poison) to the Wither Skeleton code, then changing the effect to Wither.
Or make it heal them >🙂
Logic at it's finest.