Cheato Codes
Cheato the cheat book supplies codes that double your item capacity and that afterwards can be used to fill your items back to the max. He's found in three separate places in Gruntilda's Lair, and he gives you three codes:
BLUEEGGS - The first Cheato is found behind the entrance to Bubblegloop Swamp. Enter the swamp and turn into the alligator. Exit to Gruntilda's Lair, still as the alligator, and go to the tunnel behind the swamp entrance. When you enter the room covered with snow, hang a left and go into the tiny tunnel. There, Cheato will tell you the code that will raise your egg capacity to 200.
REDFEATHERS - The second Cheato is found in the back of the lava room. Enter Mad Monster Mansion, turn into the pumpkin, and exit to Gruntilda's lair, still as the pumpkin. Go across the thin and curving path towards Brentilda and the little hole. Go in the hole and Cheato will tell you the code that will raise your red feather capacity to 100.
GOLDFEATHERS - The third and last cheato is found high above Rusty Bucket Bay. In the room that leads to the Click Clock Wood room, there is a cave in the wall. There are three pipes in the cave. Break into the middle one and you will find a switch that raises the water to the highest level. Pound the switch, quickly swim to the Rusty Bucket Bay room, hang a right, and swim up to the now reachable stairway. You must hurry while swimming there, as you only have thirty seconds to do it. Climb the stairs and Cheato will tell you the code that will raise your gold feather capacity to 20.
BLUEREDGOLDFEATHERS - After earning all these codes, you can refill all your items at once by entering this code.