Fly is a special type of Move that permits the entity to ignore any Height values on the section border (in combat scenarios). In exploration, Fly can bypass most Climbing Obstacles and may permit other traversals that would otherwise be impossible.

An entity with the Flying property may Fly with their normal Move. This is most common in exploration scenarios.

In combat, the DM may determine that an entity that can Fly essentially at will is able to stay above the ground. This can result in three-dimensional positioning, which can be quite frustrating and should generally be avoided. More commonly, an entity may use this to avoid effects on the ground, fly above the water to avoid swimming, etc.

Generally, entities shouldn't be allowed to perform attacks and then fly up out of reach unless an entry explicitly grants such function. This is particularly cheap in a turn-based game and tends to break the model.