MagMax is a side-scrolling shooter in which the player controls the eponymous MagMax, a ship capable of transforming into a giant robot should it reconnect with its various pieces found across each level. The game switches from an isometric view while on the surface to a more standard side-scrolling view whenever MagMax travels underground.
When MagMax finds a piece of its robot form, the piece joins onto the ship and provides the player with additional firepower. It will also take a hit and be destroyed in place of the player's ship, providing a secondary use as a free hit. Should the player find all the pieces, the MagMax's robotic form is quite formidable in combat and can even change its main weapon between a laser drill, fireballs and other powerful weapons.
The game was Nihon Bussan's first NES title. Nihon Bussan was, at the time, a minor player in the Arcade market, producing games like Terra Cresta. They would continue producing NES titles for much of the system's lifespan.
In April 2015, the Arcade version of MagMax was released on Japanese PSN by Hamster, joining their Arcade Archives collection.