World seventy-seven is with three ice boxes, and three already put at place boxes.
Step by step solution
Go RIGHT, DOWN, DOWN, DOWN, DOWN, DOWN, DOWN, RIGHT, push RIGHT, RIGHT, go DOWN, RIGHT, push UP, UP, UP, go LEFT, UP, UP, RIGHT and push UP.
Go DOWN, LEFT, DOWN, DOWN, RIGHT, push UP, UP, go RIGHT, push DOWN, DOWN and DOWN.
Go LEFT, DOWN, LEFT, LEFT, LEFT, LEFT, UP, UP, RIGHT and push DOWN.
Go LEFT, DOWN and push RIGHT. Go RIGHT, RIGHT, DOWN, RIGHT and push UP. Go LEFT, LEFT, LEFT, LEFT, UP, UP, UP, UP, RIGHT and push DOWN. Go DOWN, DOWN, LEFT, DOWN and push RIGHT. Go RIGHT, RIGHT, DOWN, RIGHT and push UP.
Go LEFT, LEFT, LEFT, LEFT, UP, UP, UP, UP, UP, UP, RIGHT and push DOWN. Go DOWN, DOWN, DOWN, DOWN, LEFT, DOWN and push RIGHT. Go RIGHT, RIGHT, DOWN, RIGHT and push UP.
Go DOWN, RIGHT, push UP, UP, UP, UP and UP.
Congratulations. You have completed world seventy-seven. Get ready for world seventy-eight.