Based on GodzillaZero-One's Hebimizu blog post, so credit goes to him.
The Sharkosuchus is a kaiju that plans to be released in a game sharing the same name as the monster.
The Aquatic Terror
Fused shark and crocodile
Occasionally other Sharkosuchus
The name Sharkosuchus is a pun on the prehistoric crocodile's name, and the biggest found crocodilian to date, Sarcosuchus.
The Sharkosuchus appears to be a large crocodile with very thick back legs. His forelimbs are bult more as hands, like Gamera. In between the limbs on both sides, there is a pectoral fin, and built on the back is a large dorsal fin.
A Great White was battling a Saltwater Crocodile ferociously, bringing the battle by a large volcano. Without warning, the volcano erupted, destroying itself in the process and knocking out the battling shark and crocodile. The two woke up near an island, where they were somehow merged together in a nuke.
The Sharkosuchus is usually dormant resting by underwater volcanoes. When awakened in a large eruption, it will swim to a random town before resting on shore or near it. If bothered by the military, the Sharkosuchus will go on a rampage through the city, leaving everything in ruins before wading back into the ocean, swimming towards a new submerged volcano, or, in rare case, the same one(this occurs if they either enjoy the spot a lot).