The Thorny Devil was a mutation caused by nuclear testing at Area 51 in the 1950's. It broke free of the underground environment along with the Giant Armadillo. While the armadillo was captured before it could escape the facility wall, the Thorny Devil remained under the soil, trying his best to burrow away. Randy Hernandez and Dr. Candace Kirk, the base’s overseer, came across the creature and called for unsuccessful backup from H.E.A.T.. When the others came to their rescue, the Thorny Devil crushed their jeep and attacked with its spikes. Godzilla, sensing his friends' peril, burrowed under the perimeter wall to fight the Thorny Devil. Thorny Devil's hide proved too tough for Godzilla's Atomic Ray, and he shot his Toxic spikes at his attacker. Seeing its chance, the creature made a move for the gates, ready to ram them as the humans tried to think of a way to stop it.Randy was then chosen to deliver a specially made tranquilizer dart into Thorny Devil's underbelly. Armed only with the tranquilizer gun, he caught up to Thorny Devil and shot the dart, but it fell out of Thorn Devil's skin. By that time Godzilla had recovered enough strength to battle the Thorny Devil once more. Godzilla was able to flip Thorny Devil onto his back and slay him with his Atomic Ray.
Thorny Devil has an endless supply of eject-able spikes loaded with the toxic equivalent of 20 scorpion stings.
Thorny Devil can skewer objects at short distances with its spiked tongue.