The Yenaldooshi can emit a powerful purple ultrasonic howl by opening it's quadra- hinged muzzle.
The Yenaldooshi has enhanced senses of smelling and hearing, as well as enhanced agility, speed, and strength.
The Yenaldooshi first appeared in Benwolf, where it was sent by Dr. Vicktor to steal communications equipment from a Navajo Indian reservation. Ben, Gwen, and Max were visiting the reservation at the time, and encountered the Loboan. At first, it was believed to be a Navajo werewolf, hence the name it was given. Ben first fought the Yenaldooshi as Wildvine. During the battle, he was bitten. When the Omnitrix timed out, the Yenaldooshi attacked Ben and inadvertently scratched the Omnitrix, causing the device to become stuck between Capture Mode and Active Mode. This caused Ben to undergo a gradual transformation into Blitzwolfer, as the DNA from the Codon Stream was unable to be used all at once. However, everyone believed that Ben was actually turning into a werewolf. They tried to destroy the Yenaldooshi with a silver pendant covered in the juice of a rare cactus, but were surprised when it failed. It was only after Blitzwolfer's transformation was complete and the Omnitrix symbol appeared on his stomach that they realized that they were dealing with an alien werewolf. The Yenaldooshi later seemed to be killed in a cave-in during a second battle with Cannonbolt, but survived and the device it built from the stolen communications equipment activated without the Tennysons knowing.
In The Return, the Yenaldooshi returns with it's device, which is part of Zs'Skayr's plan to block out the light of Earth's sun.