Invoker in a Melee clip On Hit is enemy.So, how to get an attacker?The attacker may not be the player.
You should be using the "On Receive Attack" Trigger on the attacked character to deal damage. It has access to both the attacker and the attacked character.
The weapon's On Hit should be used to instantiate particle effects, sounds, and thing like that. At least that's how we designed it.
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