many years ago I used to play a flashgame where the protagonists were two balls fighting each other with different guns. You could unlock guns by playing single player, to then use them online against other players. All I can remember is that the balls were customisable, and the point was to shoot to each other jumping among these gray platforms trying to hit your opponent to make him fall down. Guns dropped randomly while playing.
I have tried making a small copy of the game (except of the colors and the background) and it's something like this:
https://i.imgur.com/FpDDEKP.gif
Can anyone help me find this game? What is this game's title?