Griselbrand is banned in commander and broke all other formats including legacy, yet Griselbrand is legal in Brawl. Griselbrand is pay 7 life to draw 7 cards and Griselbrand is 7/7 with lifelink , so he's net positive to play... he's insanely strong, hence the ban in commander. Why is he allowed in Brawl??

If you can get Griselbrand into your graveyard, it's possible to reanimate him in turn two.