Okay - I'll bite on this one - WHERE is Crabbyland ?????????? - sounds like offline fun mission/practice.

HP51
CrabbyLand was just a Custom Arena lovingly named "CrabbyLand"
I had oodles of staged missions ranging from objective based to just flat-out brawls... The most valuable part was the ability to bring friends to train against the AI... Since there's no hard feelings against AI's and was always a good laugh....
Now-a-days we have to play "Operation Kill The Crab" in order to fulfill the fun until they give us Custom Arenas again
It was fairly heart-warming to be able to fill the arena to maximum number of users just to waste some time!