Here is the full list of all 8 UBERMOSH:BLACK achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
SCORE 600+
CHANGE GAME MODE
SCORE 300+ CATALYST CLASS MOD
SCORE 300+ WARLOCK CLASS MOD
SCORE 300+ GUNNER CLASS MOD
SCORE 300+ KENSAI CLASS MOD
SURVIVE AN EVENT
SCORE 300+ NO CLASS MODS