Batman: Return of the Joker

SZXZONSE        Protection from enemy bullets
SZSZKXSE        Protection from collisions
SXSATXSE        Protection from "electric grids"
AEXILGZA        Start with 1 life
GVXILGZA        Start with 100 lives
GAVXVLZA        Each Backpack Energy Capsule counts as two
AAVXVLZE        Each Backpack Energy Capsule counts as four
AAKOPIZA        Invincibility lasts until next stage
GEOSPKVN        Start with 7 Backpack Energy Capsules instead of none
GEOSTKTA        Start game with 3 life increments instead of 8.
GASOTOTA        Continue game with 3 life increments instead of 8.
SZXSZSVK        Infinite lives
GXEUIOSE        Don't get stunned when hit
AEUUAPGA + GXKLAOKE     Stand your ground!
With the last code, you may get stuck or die if you knock back into a wall
VNULTONN + PEUUGPAA     Intense knock-back when hit!