11. Half-Life 2: Survivor – June 2006

An arcade-only Half-Life game is weird. An arcade-only Half-Life game developed by Taito and released exclusively in Japan is even weirder. But that’s exactly what Half-Life 2: Survivor is and it’s all so… strange. It includes an odd multiplayer mode not seen in any other Half-Life game, some cut content from Half-Life 2, like a sniper rifle, and a lot of zombies. It’s not a bad arcade game, but it’s almost impossible to compare to the rest of the games on this list, so it ends up here. A weird novelty.