Hakkun appeared from the game "Hakkun Sutte" (すってはっくん) Hakkun has the ability to suck bricks, to get the paint out of them (if they are colored.) and if the bricks are clear, hakkun will become the brick (he can also become a ball of paint, too) but now, since hakkun has a beak, they are able to stab enemies.
The music is from Stage 1 (from Hakkun Sutte/すってはっくん)