A type of tower defense before the genre really existed, Rampart mixes Tetris-like puzzle building with strategy. The puzzle element comes in the form of various shaped blocks, which you have a limited amount of time to fit together to create a solid perimeter around your castle. Then it’s off to battle, where you blast your opponent’s newly bolstered defensives while staving off as much damage as possible. Then it’s back to defense—hopefully expanding the range of your perimeter rather than just rebuilding parts you just lost. Like all good puzzle games, Rampart is easy to learn, but success takes a lot more nuance.