Leprechaun's Revenge is an expansion for what is simply the bestest and most funnest card game in the world, Redshirts.
Redshirts is a fast paced screw-your-buddies style card game for 2 to 6 players. Technically you can play with more, if you have extra cards from expansion sets.
Redshirts is a card game set in a universe similar to, but legally distinct from, many sci-fi franchises. The goal is to be the first player to run out of crewmen because everyone knows the captains of boring voyages don't get promotions. You do this by sending them on missions they are not trained for, taking away vital equipment at the last second, and occasionally, just shooting them in the back and shoving them out an airlock.
Redshirts 2: Leprechaun's Revenge is an expansion, offering a new set of cards, featuring the evil protagonist, Leprechaun. (Don't worry, there's lots of other stuff in there too.)