Description: At the 25 second mark, a rider attempts to move on a cliff. The movement is valid because the enemy rider unit is hidden in the fog of war (as seen at 21 sec). Upon attempting to enter the tile, the movement is of course no longer valid. The rider must stop in a tile already occupied by a friendly unit. At this point this second rider unit becomes unselectable (as seen after 43s).

Expected Behaviour: 

a) The second rider should remain selectable and capable of moving out of the tile;

or

b) Upon uncovering the invalid path, the moving rider unit should reset to the closest empty tile that it took along its path. In this case the closest valid empty tile is its original location (this is Civilization's 6 solution to the issue).

Secondary Issue: There's no visual cue informing the player a unit was found and movement is no longer valid. This should also probably be addressed.