It seems Xbox360Achievements.org somehow got their hands on the achievement list for an upcoming Xbox LIVE game on the Windows Phone. That game is MonstaFish, while we tried to search for any extra information on the Internet about it, nothing is available. Judging by the title and some of the achievements, it seems the game will definitely involve various game modes. Those game modes range from typical time attack to unique modes like having your own fish aquarium and leveling up your fish.
Considering this game is pretty much non-existent on the Internet, we assume it is an exclusive Windows Phone title still in the works. Hopefully some more information will soon become available in regards to MonstaFish, an upcoming (and exclusive) Xbox LIVE Windows Phone game.