In the 3DS version, Ooze Bruiser is learned by Morrie after he invests 25 skill points into his Boomerangs skill. It costs no MP to use.
This ability is learned with 22 skill points invested into Boomerang skill and costs no MP to use.
Erik learns the skill for three points in his Boomerangs skill panel. It costs 2 MP to cast and operates exactly as before.