I used to play this game 10 years ago, so I would expect it's from the late 90's or the early 2000's .
basically the game is about 2 men or monsters one of them is green and the other is light blue , its played as a single player or split screen multiplayer, you walk on a 2d scale and there are dogs walking on the ground above you , to eliminate the enemies you have to hit the ground with your head which they are walking on i also remember one of the bosses in this game is a dinosaur waling very fast and hard to beat he was on an ice stage
basically the game is about 2 men or monsters one of them is green and the other is light blue , its played as a single player or split screen multiplayer, you walk on a 2d scale and there are dogs walking on the ground above you , to eliminate the enemies you have to hit the ground with your head which they are walking on i also remember one of the bosses in this game is a dinosaur waling very fast and hard to beat he was on an ice stage