From the badge you get this reason for gaining the badge Make a Crab Happy Played all 20 Music Blocks for the Crab, then rocked his crustacean world by playing him the moldiest oldiest of the bunch However I dont have all 20 music blocks. So perhaps the award should read:- You played a music block for the crab 20 times then rocked his crustacean world by playing him the moldiest oldiest of the bunch.