Prime Invader Zoda is the main antagonist of the StarTropics series, being one of the few characters who appeared in both StarTropics and Zoda's Revenge: StarTropics II in which he appears as the titular villain. He is a horned, shadowy alien who wishes to find the Three Magic Cubes, only to be thwarted by Mike Jones. He destroyed the planet Argonia and is trying to finish off the remaining Argonians which are Mica and her siblings. He is finally destroyed by Mike in Zoda's Revenge: StarTropics II, thus bringing the world to peace.
In the original StarTropics, the player fights Zoda twice, once in his "Zoda Manifest" form and another in his "Prime Invader Zoda" form, which is the second to last and final boss of the game, respectively. The Laser Gun is the only thing potent enough to damage Zoda Manifest, who uses his large hands to attack Mike Jones. After defeating Manifest, he'll reveal a more menacing form that shoots bullets from his belly. If the player is touched by Prime Invader Zoda once, they'll lose a life.
In Zoda's revenge you'll fight three of Zoda's clones. The forms include Zoda-X of chapter 4, Zoda-Y of chapter 7, and Zoda-Z of chapter 9. Each clone is increasingly harder than the previous incarnation. Zoda-X is green and will throw skulls at the player and create rings of fire that surround Mike. Zoda-Y is also green though will transform into an owl like creature midway in the battle. Zoda-Z is purple and is the final boss of the game, having attacks suck as spawning miniature Zodas and turning the player into a pig for a short time.