This is a ToolAssisted Speedrun. All actions are doable realtime with practice, but for this video time was slowed down and errors were redone to create one stream of nearperfect play. No cheats or hacks were used.
A door movement glitch allows some fun in Blaster Mastereven in the USA rom, it can be used to skip Area 4 entirely. For the Europe version, though, it gets better: When inserted into a wall, Jason doesn't get stuck; he zips upward at a whole tile per frame. Further, at any time, pausing the game will reset Jason's momentum, and, for one precise frame, allow the player to jump again in midair. Between these two glitches, I have figured out how to defeat Blaster Master without fighting any of the bosses other than the final area's pair.