World four hundred and twenty-eight is almost symmetric puzzle with many boxes.
Step by step solution
Go UP, push RIGHT, RIGHT, go DOWN, push RIGHT and RIGHT. Go UP, push RIGHT, RIGHT, go DOWN, DOWN, RIGHT, RIGHT, UP, UP, UP and push UP. Go DOWN and push RIGHT. Push UP, go DOWN, LEFT, DOWN, DOWN and push RIGHT. Push UP, go RIGHT, push UP and UP. Go DOWN, DOWN, LEFT, DOWN, LEFT, DOWN, DOWN and push RIGHT. Push DOWN, go UP, LEFT and push DOWN. Go UP, UP, UP, RIGHT, push DOWN, go RIGHT, push DOWN and DOWN. Go UP, UP, LEFT, push DOWN, go UP, UP, UP, RIGHT, push DOWN, DOWN and DOWN. Go UP, UP, UP, LEFT and push UP, go DOWN, DOWN, DOWN, LEFT, LEFT, LEFT, DOWN, push RIGHT, go UP, RIGHT and push DOWN. Go UP, LEFT, LEFT, UP, push RIGHT, RIGHT, RIGHT, go DOWN, RIGHT, push UP, UP and UP. Go DOWN, DOWN, LEFT, LEFT, LEFT, LEFT, UP, UP and push RIGHT.
Push DOWN, go RIGHT and push UP. Go DOWN, LEFT, push DOWN, DOWN, go LEFT, DOWN, push RIGHT, RIGHT and RIGHT. Go LEFT, LEFT, LEFT, UP, UP, UP, LEFT, LEFT, DOWN, push RIGHT, RIGHT, RIGHT, go UP, RIGHT, push DOWN and DOWN. Go LEFT, LEFT, UP, LEFT, LEFT, LEFT, LEFT, UP, push RIGHT, RIGHT, RIGHT, RIGHT, RIGHT, RIGHT, RIGHT, go DOWN, RIGHT and push UP. Go LEFT, LEFT, LEFT, LEFT, LEFT, LEFT, LEFT, LEFT, LEFT, LEFT, UP, UP, UP, RIGHT, RIGHT and push DOWN. Go RIGHT and push DOWN. Go UP, LEFT, UP, LEFT, LEFT, DOWN, DOWN, DOWN, RIGHT, RIGHT, push RIGHT, RIGHT, RIGHT, RIGHT, RIGHT, RIGHT, go DOWN, RIGHT and push UP. Go LEFT, LEFT, LEFT, LEFT, LEFT, LEFT, UP, UP, LEFT and push DOWN. Go UP, UP, LEFT, LEFT, DOWN, DOWN, DOWN, RIGHT, push RIGHT, RIGHT, RIGHT, RIGHT, RIGHT and RIGHT.
Go DOWN, RIGHT and push UP. Go LEFT, LEFT, LEFT, LEFT, LEFT, LEFT, LEFT, LEFT, DOWN, push RIGHT, RIGHT, RIGHT, RIGHT, RIGHT, RIGHT, RIGHT, RIGHT, go UP, RIGHT, push DOWN and DOWN. Go LEFT, LEFT, LEFT, UP, LEFT, LEFT, LEFT, LEFT, LEFT, LEFT, DOWN, DOWN, DOWN, DOWN, RIGHT, RIGHT and push UP. Go RIGHT, push UP, UP, go LEFT, UP, push RIGHT, RIGHT, RIGHT, RIGHT, RIGHT, RIGHT and RIGHT. Go LEFT, LEFT, LEFT, LEFT, LEFT, LEFT, DOWN, DOWN, RIGHT and push UP. Push RIGHT, RIGHT, RIGHT, RIGHT and RIGHT. Go LEFT, LEFT, LEFT, LEFT, LEFT, LEFT, UP, push RIGHT, RIGHT, RIGHT, RIGHT and RIGHT. Go LEFT, LEFT, LEFT, LEFT, LEFT, LEFT, LEFT, LEFT, DOWN, push RIGHT, RIGHT, RIGHT, RIGHT, RIGHT, RIGHT, RIGHT and RIGHT.
Go LEFT, LEFT, LEFT, LEFT, LEFT, DOWN, DOWN, LEFT, push UP, go DOWN, DOWN, LEFT, LEFT, UP, UP and push RIGHT. Go UP, push RIGHT, RIGHT, RIGHT, RIGHT, RIGHT and RIGHT. Go LEFT, LEFT, LEFT, LEFT, DOWN, DOWN, LEFT, push UP, UP, go LEFT, UP, push RIGHT, RIGHT, RIGHT, RIGHT, RIGHT and RIGHT. Go LEFT, LEFT, LEFT, LEFT, LEFT, DOWN, DOWN, DOWN, DOWN, LEFT, push UP, UP, UP, UP, go LEFT, UP, push RIGHT, RIGHT, RIGHT, RIGHT, RIGHT, RIGHT, RIGHT, RIGHT and RIGHT.
Go LEFT, LEFT, LEFT, LEFT, LEFT, LEFT, LEFT, LEFT, LEFT, UP, push RIGHT, RIGHT, go UP, RIGHT, push DOWN, go LEFT, DOWN, push RIGHT, RIGHT, RIGHT, RIGHT, RIGHT and RIGHT. Go LEFT, LEFT, LEFT, LEFT, LEFT, LEFT, UP, UP, UP, LEFT, push DOWN, DOWN, go LEFT, DOWN, push RIGHT, RIGHT, RIGHT, RIGHT, RIGHT, RIGHT and RIGHT.
Congratulations. You have completed world four hundred and twenty-eight. Get ready for world four hundred and twenty-nine.