Planet Monsters uses a style that is very reminiscent of Bomberman. As I said before, there is really nothing here that is going to make you wet yourself in excitement. Your monster, which resembles a furry hot dog with big feet, is animated very smoothly and even manages to show a few facial expressions - such as this evil looking smirk when he gets his hands on a jelly gun. The enemies are animated just as smoothly and show a little more creativity in their design. As you progress through the levels, the monsters start off in a simple 'baby' form, but as the level progresses they begin to evolve until they reach their final stage - which of course, is the level boss. While this was really cool to see, I couldn't help to feel cheated that my monster always stayed the same and looked as stupid as he does. It would have been a real boon to the game if your character could evolve as well.
Sound is about as simple as the graphics, with the only noticeable thing being the music. It's nothing memorable but it works well with the game.