Force Feedback from animBP?

Hey, so i was trying to make my controller rumble when i attack, and since i want a different rumble on every attack (Its a sword melee game) i dont wanna cast variables between animBP and the CharacterBP because that will be tons of variables.

So i was thinking of casting from animBP to the main character but i get this error:

Maby its because i need to cast from main character to the animBP. But i dont know what to plug in to the “Object” pin on the “Cast to MainCharacterAnimBP”

Can someone help me i’d be very pleased! ^^