Floating

Floating: A fairly uncommon ability, usually seen from ghosts or spiritually enlightened, making them immune to some attacks and spells. The description is wrong in that the ability does not allow the crossing of rivers.

Floating works underwater.

Specifically, floating allows:

Despite the description, Floating does not in fact allow crossing rivers, as shown by the following image using FIXME-Multi-Turn Movement. Notice how the closest path to the province across from the river is not by passing over the river but by going around it: