SA4T-DE1A
Infinite energy (may have to turn OFF to kill bosses).
AJZA-AA8W
Infinite continues.
BFJA-AADG
Start with 9 continues.
AECT-ACA0 + 6ACT-AKT2
Start a new game with the strongest (level 3) Flame ring
and the strongest (level 3) Barrier ring. This code
causes minor graphic problems, but doesn't seem to hurt game play. You can modify this code to let you start
with other rings: AECT-ACA0 + 6JCT-AKT2 lets you start
with the Earthquake ring and the Double Jump ring.