Gun Brothers is an action platformer that sees you playing one of a number of gun-toting characters. There are different classes, and you'll unlock more as you play along. Whoever you're playing as though, the idea is the same - shoot everything and don't get shot.
You get crates when you complete missions, and inside of those you'll find new gear. Stick it on your team and they'll get tougher, getting them ready for the difficulties ahead. You'll need to upgrade them as well, using dog tags that you're rewarded as you fight.
Different enemies have different patterns of attack, which is great when you're fighting them one on one, but once there's more than a few on the screen you're going to be jumping and running your way through storms of bullets from every angle.