It's weird. At first, you aren't sure what's happening on the screen. Slam Bolt Scrappers involves two teams floating around, beating up on each other, fighting demons -- who then proceed to turn into colored blocks -- and using said blocks as if they were playing Tetris.
Once enough blocks of the same color touch, a turret is formed; these can either defend or attack, but ultimately, the goal is to eliminate the enemy team's blocks. All of them. This means battles can go on for quite a while, and there's more than enough room for comebacks.