To me, Serious Sam feels more like a 3D version of Robotron: 2084 than a traditional FPS. Very high numbers of simple enemies, enclosed featureless arenas and l

To me, Serious Sam feels more like a 3D version of Robotron: 2084 than a traditional FPS. Very high numbers of simple enemies, enclosed featureless arenas and large open spaces, interactions between the various enemy types forcing improvisation instead of memorization. Robotron is a great game, so this is a clever way of designing interesting fights without needing to spend a long time on map design. The later games switched to a more traditional FPS style, but the original is something unique and I highly recommend playing it.