Increase Damage times 100:
Hold R1+R2 then press Up, Down, Up, Down, Left, Right, Left, Right.

Full Health and Mana:
Hold R1+R2 then press Left, Left, Right, Right, Up, Down, Up, Down.

Enemy Attacks Pass Through Bard:
Hold R1+R2 then press Left, Right, Left, Right, Up, Down, Up, Down.

Unlock All Levels:
Hold R1+R2 then press Right, Right, Left, Left, Up, Down, Up, Down.