Anti-TD is a fun take on Tower Defense games: you play the never-ending march of invaders, and the computer places the towers.
I’ve talked a lot in the past about how games can be symmetrical or asymmetrical. Symmetrical games are ones where the capabilities of the player are comparable to the capabilities of the opponent: tennis, Quake, chess. Asymmetrical games are ones where the player and the opponent have differing games to play. This latter form really flourished with the advent of computers, but examples do exist from prior; for example, baseball or cricket can be viewed as alternating rounds of asymmetrical gameplay, and board games like Fox & Geese are asymmetrical.
