The classic extraterrestrial hunting X-Com series just hit Valve's digital distribution service Steam today. For a low, low price, you can download two amazing strategy games and their completely horrific sequels!

X-COM: UFO Defense, X-COM: Terror from the Deep, X-COM: Apocalypse, X-COM: Interceptor, and X-COM: Enforcer are all available now for $4.95 apiece, but you can also buy the complete series all at once for $13.49. Math would tell you that the complete pack is the better deal but I must warn you that Apocalypse, Interceptor, and Enforcer are all extremely bad.

UFO Defense and Terror From the Deep, however, are extremely detailed strategy games that put you in charge of a secret agency that guards Earth against extraterrestrial threats. You built up the agency's bases, researched new technologies, and equipped your soldiers and vehicles with armaments. When an extraterrestrial craft appeared, you would send troops out to attack it, and at this point it would turn into a turn-based strategy game. Interceptor moved to real-time strategy, which sort of sucked, while Interceptor and Enforcer ditched strategy altogether and focused on being a shitty flight sim and FPS,respectively.

Anyway, the first two are must-plays so don't miss them, anyway. They'll make you realize why all of us old-timers have been getting all hot and bothered over the rumors that Ken Levine and 2K Boston are now making a sequel.