http://www.playonline.com/pcd/topics...91/detail.html
So this anniversary event is cccrab battle! For the red crab mount or something blah blah. But the real prize is in the chest next to the moogle is a bunch of free stuff like previous anniversary prizes... including vana clock and kupofried.
Pretty easy minigame. Use emotes to change the emotion bar of the crabs that you approach to match yours closely. Gotta be fast as they run away after about 3 tries. You earn grind and boy is it as it's 500 points for the mount and winning most of them looks like about 2 points each and I was getting around 30 a run
Some of the things you can buy with "grind" the currency you earn from this are of course the mount, SP keys, AMAN vouchers, ambuscade KIs and stupid fireworks