Oh yeah, isn’t he the guy who collected the dragon balls and became the wizard king?

No, you're confusing him with Rimuru. He is the guy whose sister turned into a demon and is on a journey to find the One Piece.

Ah

I thought Rimuru was on a quest to find the Philosopher's Stone and kill all criminals

No, that's Tohru, the one who's going to become the greaatest hero in the world

no thats narito you dummys!

the one that was a jiraki and became the 7th hokaga