The idea, at the time, was that we could create some extra layered complexity by having cards that could take advantage of the fact that most creatures have two creature types on them
The X/Y/Z bit is a bit bizarre, the artwork isn't quite as zany as it could've been, and the flavour text, presumably, is the actual WOTC customer service number
These cards probably won't make too big of a splash beyond the set itself or special decks themed around taking advantage of their creature types, but the third card has a little bit more potential to stand out in my eyes
MtG has five colors arranged in the so-called color pie you see on the back of the cards: white, green, blue, red and black
This is another card that can help you ramp ahead and stay ahead of schedule, even when your opponent is flush with removal spells