This unit ignores restrictions and penalties imposed by terrain and may move across chasm spaces without dying. This unit has two additional ranks of Sentry and is immune to the effects of Lumbering unless Grounded
In general, champions with flying usually cost more, but they are great for mobility.
Note Flying allows champions to move across chasms, lava, and Impassable terrain, which most units have to go around. This allows them to reach fonts and other squares faster than most champions on some maps.
Also note that some runes and abilities cause Grounded which means the champion loses Flying temporarily. This can be a problem when over these types of harmful terrain.