It seems a bit odd to me that the rock roll, which is a directional ability, has a circle you can move around as it's targeting icon - it can be a little difficult to see where the rock is going to go - alternatively, it could be an arrow or dotted line extending from your rook out to the maximum range of the rock roll, in the direction of your cursor - would make it easier to target groups of enemies, whilst still allowing you to target a single enemy if desired