World five hundred and four is with two boxes for movement over a fence created from placed boxes.
Step by step solution
Go LEFT, UP, UP, RIGHT, RIGHT, RIGHT, RIGHT, RIGHT, push UP and UP. Go DOWN, DOWN, LEFT, LEFT, LEFT, LEFT, LEFT, DOWN, DOWN, RIGHT, RIGHT and push UP. Go DOWN, LEFT, LEFT, UP, UP, RIGHT, push RIGHT and RIGHT.
Push UP, UP, go LEFT, LEFT and push DOWN. Push RIGHT, go DOWN, DOWN, DOWN, LEFT, LEFT, UP, UP and push RIGHT. Go LEFT, DOWN, DOWN, RIGHT, RIGHT, UP and push UP. Go LEFT, UP, UP, RIGHT, RIGHT, RIGHT, RIGHT, DOWN, DOWN, push LEFT and LEFT.
Push UP. Push LEFT, go RIGHT, DOWN, RIGHT, RIGHT, UP and push LEFT. Go UP, UP, UP, RIGHT, push DOWN and DOWN. Go LEFT, DOWN, DOWN, LEFT and push LEFT. Go UP, UP, push RIGHT, go LEFT, DOWN, DOWN, RIGHT, RIGHT, UP and push UP.
Go LEFT, LEFT, DOWN and push RIGHT. Go LEFT, UP, LEFT, LEFT and push DOWN. Push RIGHT and RIGHT. Go DOWN, DOWN, DOWN, LEFT, LEFT, UP and push UP.
Go DOWN and push RIGHT. Push UP, go DOWN, DOWN, RIGHT, push UP and UP.
Congratulations. You have completed world five hundred and four. Get ready for world five hundred and five.