It was a 2D giant robot fighting game, where you could see the pilots climb inside the robots before the battle. There were different kinds of robots and though I'm not too sure I think there were purchasable upgrades as well
The game WASN'T One Must Fall, I still play OMF but the game I'm thinking of is a different one.
The first one to remember the game and tell me the name will get 10USD worth of GOG's, freely choosable by the winner. If no one can succesfully guess the game, I'll just pick a winner at random from those who tried their luck at this. If I think that someone guesses the game too quick I'll just give another game free from the interplay promo to whoever posts in this topic AFTER the winner has been announced.
EDIT: I must clarify that you can only guess the name of the game (do not use a list to enter), only 1 guess per person :) I can give you a hint, the game was from the Amiga/PC era, I doubt it was released for consoles