It was the coolest game in it's day. Beat the pants off mario. There were five "main" episodes. 1-3 were oldschool, NES level graphics. 4-5 were really revolutionary at the time. With multiple background layers that scrolled bast, characters that weren't confined to "blocks" and my favorite... Keen, if he came up short on a jump, could GRAB ONTO AN EDGE! I mean, seriously? Didn't you always hate hitting mario's toe on the far ledge and then sliding into the abyss? Oh, and keen had guns, a hilarious plot, and a pogo stick! Oh, and it's own alphabet, which was a simple 1:1 mapping to english. So if you learned 26 symbols, you could read "galactic alphabet" the same speed you read english. It was a secret area to find the school-room with the translation, but if you learned it, there were all sorts of signs throughout the games that were actually useful tips. Ones that said things like "Self Destruct Button ->" and such. :-)