You'll start with a few select blocks, such as armour panels and weak guns, and bit by bit you can destroy weaker tanks, take their parts for your own machine, and then take on more powerful tanks. You've also got a little guy shoveling coal on-board to keep everything working, and he can pop out every now and again to fix up the exterior if it's showing cracks. Further into the game, you've also got saboteurs who can jump onto the enemy's tank and use their magic on it.
