Sharks are animals that live in the seas of Planet Earth and Mobius. They are one of the most ferocious marine creatures, known to have attacked humans on rare occasions and are popular dangers in fiction. They are often characterised by their sharp teeth, streamlined bodies and their predation.
- Sharks are known as ripteeth in the Ecco the Dolphin series. Four of them ambush Ecco in the first part and are close to killing him when a killer whale comes and saves him, scaring off the enemy.
- Trident, of the Eternal Champions, supposedly lost his arm in a fight against a shark. It was replaced by his namesake.
- A shark chases Casey and Brad as part of the Wildside game in Kid Chameleon story Back to Unreality!. The fish attacks them after Cyclone creates a thunderstorm. Brad almost leaves Casey to die, but plucks him out of the water at the last minute.
- Sharks are major villains in Captain Plunder story Shanghaied. Proctor Speckle is made to walk the plank after robbing his personal stash and is faced with three hungry sharks. His serum transforms him into Mr Fry, easily enabling him to fight off his foes. However, some of the potion slips into the sea into the mouths of more sharks, turning them into super-powered warriors. The Sky Pirates are unable to fend them off and Fry turns back into Speckle, so Simpson the Cat is left alone in the fight. When they also turn back to normal, Plunder throws them in the hold for a snack later.
- Plunder's old foe returns once more in following story Captain Plunder and the Spice Maidens. When Plunder is laden with The Curse of Akotek, Plunder feels he is safer by riding a small boat behind his ship, but is stolen up on by a ferocious shark.
- Hammerhead is a criminal entrepeneur from New Tek City in the Special Zone. The fierce shark tricked Porker Lewis (then known as Oscar the Pig) into creating a nuclear bomb, although his plans were destroyed before it could be built. Hammerhead was revealed to be a crook, but it didn't stop his ferocious nature or his snappy dress sense. Upon being reunited with Oscar, Hammerhead easily dealt with Knuckles the Echidna, Mighty the Armadillo and Espio the Chameleon before being arrested by Lieutenant Furor.
- Sharka Khan was the former Zone Leader of Trituna, an underwater Zone on Mobius. When approached by Agent X with a plan to defeat Sonic the Hedgehog, Khan sends his best warriors to the Beanson Coast Zone. Things go badly wrong and Khan tries to flee, but is discovered and kicked out of his job. Jaws Michael also appears to be a shark, though may be a piranha.
- Sonic the Hedgehog is chased by a shark on the cover of Sonic the Summer Special 2009.
- The Zone Leader of the Seaside Hill Zone is a shark. Unlike most other sharks on Mobius, the Seaside Hill Zone Leader is a land animal and doesn't appear to require any water.
- Jawz is a shark-like Badnik that can propel itself through air and water like a torpedo. Upon striking its enemies, it explodes, killing the organic battery inside.