"Jeff the land Shark" real Name Jeffrey, was among the Land Sharks created by M.O.D.O.K and was Adopted by Gwenpool in West Coast Avengers 3.

He's as the name implies, a land shark, he walks on land and breaths air, but can also breath in water, and as shown in Marvel Rivals game and connected comic, can swim in the ground somehow...

He's the main character of "It's Jeff: Infinity Comic" and "Venom War: It's Jeff!" He also has other more minor appearances in other comics. He's also one of the playable characters in Marvel Rivals.

(Not every image of Jeff should be tagged Marvel Rivals, only the ones featuring the outfits exclusive to the game, (though some are based on his outfits in the comics there are visual differences), unless relevant to Marvel Rivals in some other way)

Examples being; he didn't have a collar until Rivals, his comic Dolphin outfit wasn't pink or had a keychain, his Cuddly Fuzzlefin outfit was made for Rivals.