Booster Trooper, from DNS Development, is a side-scrolling 2D shooter that gives you several different weapons, grenades and a jetpack to take on a never-ending army of respawning enemies. The game is fairly basic as it only requires four direction keys and the mouse. 
The game offers four familiar modes – deathmatch, team deathmatch, capture the flag and destroy the beacon (demolition) in both single player and online multiplayer. However, I was unable to find anyone online playing the game. That’s not to say no one is playing it as there are some global leaderboards, it just seems like they don’t play often. So I was limited to the single player experience which only allows for deathmatch and team deathmatch. This is most likely due to limited AI intelligence.