https://www.gamespot.com/articles/super-mario-odyssey-see-everything-cappy-can-posse/1100-6454376/

One of the central mechanics of Super Mario Odyssey is possession. Thanks to his new companion, Cappy--a sentient hat whose abilities create a whole range of worrying questions--Mario is now able to take control of enemies and objects in his environment.

By throwing Cappy, Mario is transported into whatever the hat lands on, allowing him to assume full control. This works on everything from a lowly plodding Goomba to ... well, it's best if you see for yourself. In the video above, we've got a showcase of everything Mario can possess using Cappy. There's also a look at some of the special abilities that are available to Mario when he possesses them.