C Key Level

Enter this level on the right side of L. It is cursed. There are various electric Cyan Beetles to avoid - you can approach them to trigger their explosion to turn into a Blue Gem. Below, find a Green Gun and more electric Cyan Beetles. Beware - firing the gun will stop them from exploding.

Use a Green Gun on the Use Bomb to destroy the brick wall. Use the green gun to destroy various other enemies too. Shoot the box in the wall to deploy a couple bombs to destroy the brick walls.

Drop down. Kick your green gun down through the little gap to the right. Enter the door and push a heart and 9 coin and some bombs into the save room collector. Go through the doors and drop down. Carefully blow up the walls using the bombs while avoiding cyan gunmen.

Continue right, avoid the electric beetles. Collect a couple Black Gems with the green gun. In the final room there is the C Key, a Green Dog and a couple Save Room Bombs. Use one of the bombs to teleport yourself and everything else back to the save room.