Movable cellular automaton

A movable cellular automaton is like a game of checkers. Each cell on the game board is like a checker piece and each piece has a number. The number of each piece tells you what direction it can move - either up, down, left or right. Whenever two pieces meet, their numbers are added together and the result is used to decide the direction of the next piece. This game is a type of puzzle - the goal is to move your pieces around the game board to reach the finish line.