The monsters
The School, Mines, Play Place and WhoVille each have one named hunter; players in two Pizzeria recordings report more than one animatronic. They are not reskins of each other: the school one walks a route through rooms, the Mines one belongs to a map built around explosives rather than keys, and the newer ones are too new to have a documented pattern.
School map
The Cat in the Hat
Patrols every room on a repeating circuit. Learn the circuit and you can search behind him.
Mines map
Thomas
A tank engine on spider legs, added with the Mines chapter.
Play Place map
Ronald
The Play Place hunter, named by the developers’ own store pass. One group of players says he teleports.
Pizzeria map
The animatronics
Players in two recordings report more than one. The newest monster pass says Bon Bon, but nothing on screen has named any of them.
WhoVille map
The Grinch
Beats you to a present if you're slow, on top of the usual chase. The store's pass just calls him the Grinch.
Came here after a clip of the Cat and not sure it was this game? Roblox has several Cat in the Hat experiences. How to tell Scream And Run from the others.