Stinkfly is a playable alien.
In any situation requiring flight, Stinkfly is Ben's alien of choice. Stinkfly's thin, rapidly flapping wings allow him to move at high speeds in the air and dodge attacks just as quickly. Stinkfly also possesses disproportionate strength, enough to carry people and objects heavier than himself. Stinkfly's four eye stalks give him a wide range of vision from the sky, including the ability to look directly behind himself.
Stinkfly can excrete high-pressure streams of liquids from the pollen ducts in his eye stalks and mouth. The type of liquid can range from a flammable toxin to an immobilizing jelly
Like most insects, Stinkfly is extremely vulnerable to any kind of chemical poison or gas. Although his exoskeleton body is fairly strong, his wings are quite fragile. Water is especially a problem for Stinkfly, as it can render him incapable of flight if too much gets on his wings. Furthermore, he is unable to swim due to the small surface area of his limbs. A more minor inconvenience is Stinkfly's intense body odor (hence the name), so hiding can be a problem.