You control the angel (white disk) by clicking the target position.

You cannot click a wall.

The angel can move in the directions north, south, east, and west.

The angel slides any number of empty spaces and must land on an empty position or on a position occupied by a soul (yin-yang token).

There are 10 challenges with fixed setups and three challenges with random setups. In the random setups, you have to click the empty board first to let the system drop all tokens.

The first random setup uses 10 randomly dropped walls and 10 randomly dropped souls; the second one uses 15 walls and 15 souls, and the last one 20 walls and 20 souls.