About
Hydefos is a shoot 'em up with smooth scrolling, a rarity on the MSX, where the scrolling is usually choppy, and a feat developer Hertz had already accomplished on a previous title, action platformer Psychic World. You pilot one of five ships through levels featuring branching paths, so two play-throughs could be different depending on where you go.
Story
Planet Tiar is in crisis. The sunspots of this distant Earth-like planet's sun are disrupting its climate, and now evil invaders are taking advantage of this situation to try and conquer Tiar. The planet sends a distress signal to Earth, calling for a hero to fight the invader and save them. From the deep sea to the far reaches of space, it's up to you to fight and make sure Tiar does not fall.