It's a surprisingly good pokemon-like game for the gameboy color that isn't bad because of broken team combinations, and is actually fun because of randomly generated dungeons. No one monster is overpowered because you can always breed it with something else to produce another monster with better skills and stats, or your opponent could produce a powerful counter for that monster with breeding (I'm not sure, but I think that you can battle over link cable; I do know that you can mate monsters over link cable and get twins).
You can download it
here, or buy it in stores like stefan and me (I got my copy for $5 yesterday).
Currently stefan, RPG, and myself are all playing it, RPG having played the most because I felt like sleeping. Stefan is in some silly early dungeon like Village or Talisman, and I just cleared F class and hatched my Sky Dragon egg.
If enough people got into this, then we could compare crazy breeding combinations (there are over 40000), strategies, and hilarious experiences while sitting around the campfire and eating marshmallows.
If you need further convincing:
<PsyBorg> dude, you're playing with the king's great log and everyone's licking you
Oh, and Pickies ftw. Or rather, Pickies+Healers ftw. Perhaps PickyHealer+Anteaters ftw. Crazy fun!