[SOLVED] Is there any way to disable critical hit?

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2

DamageModifierTypes.CRITICAL_HIT is a modifier type for critical hits.

So in the event you can iterate the list of DamageModifiers and if you find one of type CRITICAL_HIT, then you can set its function to be Functions.identity() - that is, it will not modify the damage in any way. You can do that with AttackEntityEvent#setOutputDamage(DamageModifier, Function<Double,Double>) function.