 "IWBTG" is made up of several stages split into many screens, which are mostly pastiches of Nintendo Entertainment System games, such as "Tetris", "Ghosts 'n Goblins", "The Legend of Zelda", "Castlevania", "Kirby", "Mega Man", and "Metroid".At the end of each stage, a boss must be defeated to progress.The first seven bosses (Mike Tyson; Mecha Birdo; Dracula; Kraidgief, a parody of palette-hacked character glitches; Mother Brain; Bowser, Wart, and Dr. Wily in the Koopa Klown Kar; and a mix between the Mecha Dragon from "Mega Man 2" and the Yellow Devil from "Mega Man" and "Mega Man 3") are adapted from classic games, mostly platformers, but their behavior and appearance have been modified and enhanced for "IWBTG".