Hammerhead is Rubble's aquatic riding friend that made his debut in the Season 9 episode, "Aqua Pups: Pups Save the Whale Patroller".
Bio
Hammerhead helps Rubble travel underwater and push heavy objects aside when he cannot use his main Aqua Pups vehicle. He has helped him, along with the other PAW Patrol members, rescue the Whale Patroller in "Aqua Pups: Pups Save the Whale Patroller" and stop an old sunken science submarine from crashing into a coral reef in "Aqua Pups: Pups Save the Reef".
Personality
Hammerhead is friendly and likes to help Rubble out as much as he can, even if he is not strong enough (as seen in "Aqua Pups: Pups Save the Reef").
Appearance
Hammerhead has a dark gray body with a lighter gray underside, a wide head with gills on both sides, sharp teeth, two pointed fins, two dorsal fins, one being large, the other being small, on his back, and a vertical tail. He has thick black eyebrows and blue eyes.