It is fairly simple to learn (the cards pretty much tell you everything you need to know), and it is tons of fun. You basically pick two factions; the base game comes with Pirates, Dinosaurs, Aliens, Zombies, Robots, Ninjas, Tricksters, and Wizards, and shuffle them together. You then lay out different base types. You then take turns playing minions and actions on to bases in an attempt to win them and score points.
The best parts of the game is the way with the different well thought out factions play and then finding out how the different factions work together… For example, the Zombie deck will having you pulling cards out of your discard pile almost as often as your deck, giving it that undead feel. Half the fun is seeing how that tech will pair up with the uber-powerful Dinosaur faction or the action/spell filled wizard class.
The base game is great… and there are already tons of expansions packs. I look forward to getting my hands on the Awesome Level 9000 expansion in addition to some of the full stand alone sets with multiple new factions that can be played alone or mixed with the originals. Those include The Pretty Pretty Expansion, The Obligatory Cthulhu Expansion, Monster Smash, and The Science Fiction Double Feature.
I recommend this game to anyone with a nerdy streak who likes fun games. It has a similar feel to the Munchkin card games, in the way that it is silly, expandable, and just plain awesome.