Game: Shadow of the Colossus (2005)

Shadow of the Colossus set the standard for boss battles way above the norm. The entire game is a series of gigantic, larger than life fights against lumbering and massive beings rattling the land. Any of the bosses could be anywhere but the first boss represents the moment that the game asserts its uniqueness. On this boss, you'll scale the giant while trying to find its weak points to bring it down. The timing is just as important as if you screw it up, you'll go for a long tumble to the ground and will have to start all over again.