Heavy Unit: Mega Drive Special

Heavy Unit: Mega Drive Special is a side-scrolling shooter set during an alien attack on the human colony of Le Tau. Players control a special starship through six levels filled with enemies, mid-level bosses, and end-of-level bosses.

Defeated enemies can release upgrades that improve speed or weapon power, provide a shield or extra lives, or transform the ship into a robot. The robot uses a laser beam and homing energy balls instead of the standard vulcan gun, but its larger size makes it more vulnerable to enemy fire and environmental collisions. Taking a hit in robot form costs a life, removes collected upgrades, and returns the ship to the last checkpoint.

The game was released on December 26, 1990, for the Sega Mega Drive/Genesis. Its level layouts remain consistent across versions, while enemy placement, graphics, and sound differ; the Genesis version features more colors and larger enemies.