Winnie is hungry and you need to snap him out of his frenzy or end him permanently.
Smash Him
End Winnie permanently with falling pianos, endless pits, and fake walls.
Cure Him
Or you can collect honey throughout the world to restore him to his old self.
Upgrade and craft
Explore the open-world 100 Aker Woods to directly find or complete quests for black honey, which can then be used to craft new items or directly upgrade your character.
Relax
Play mini games for more black honey, like fishing.