Here's my entirely serious suggestion:
Passive 1 - 'Straight Ballin' - Vader rolls up to battle two turns late, but none of you are gonna say anything about it, are you? No, you're too afraid to do that.
During his excellent entrance, his shuttle crushes 4 enemies and 2 allies, reducing them to 1% health and putting every single debuff in the game on them. Even the freaky ones the devs probably use that do crazy stuff like making them instantly die or act out every one of their animations.
Passive 2 - 'Meta? I Just Finished Scraping It Off My Boots!' - GK took Vader's favourite leg and his slightly less favourite leg, so he instantly dies. It's justice, okay?
Also, Luke loses his hand when Vader appears, and his abilities get replaced by 1 that just lets him shout 'nooooo!', doing no damage but slightly annoying Vader.
And Rey dies too because Vader doesn't want that lady making moves on his favourite grandson, Ben Swolo.
