Cuphead

Cuphead is an old-school shooter/action game where the boss fights are a big part of the game. One or two players can take control of both characters at the same time in Cuphead. Cuphead and his brother Mugman must fight their way through a number of stages and the game's final boss in order to pay off their debt to the devil. People liked the game's art style and how hard it was.
Cuphead is mostly made up of boss fights that never ends, which are broken up by sections of run-and-gun combat. Every planet, with the exception of the very last one, features a mausoleum. Within, the players face off against ghosts on their way to a vase that grants them super if they are successful in finishing the obstacle course.

Each of these boss battles and run-and-gun levels takes place in one of the game's four distinct worlds, with the climactic showdown against the Devil himself taking place on the fourth and final planet.