Nattie (also known as Piranha) was a cross-species mutation that appears in the video game, The Amazing Spider-Man.
As opposed to most cross-species experiments, which were usually the result of one scientist in his lab, this piranha infused with human DNA was the product of a team of Oscorp scientists working from Curt Connors’ research. Though only loosely associated with the group, Dr. Mendel Stromm took to calling this experiment “Nattie”, based on the subject’s scientific name, Pygocentrus nattereri. Stromm’s colleagues found great humor in the contrast of such a nonthreatening name belonging to one of the most ferocious fish on Earth, and the moniker caught on.
Beyond Nattie’s odd name, the beast’s story is about as straightforward as it gets. No one even bothered to record the identity of the human donor, so it is impossible to observe whether or not Nattie has taken on any of his “father’s” traits.
All signs point to Nattie’s human half coming from a brute fighter, as he’s surprisingly brutal on land, where his charge attack is second only to Rhino’s. He can even follow this up with a deafening scream capable of knocking even Spider-Man off his feet. And when Nattie confronts its prey under the water, its next victim doesn’t stand a chance.
Encounter with Spider-Man
While in the sewers searching for Connors (now turned Lizard), the super hero Spider-Man encountered Nattie and his mutated Pygos in a huge, cylinder-like room filled with water. Knowing he doesn't have a chance at finding Connors - much less defeating Nattie - under water, the intelligent hero decides to turn off the water supply for a moment in order to get the upper hand on the creature and its minions. After many wheels turned and many Pygos defeated, Spidey turns the water off one last time to finish off the cross-species by webbing him up to the wall above. Spider-Man then continues his search and leaves.
Nattie manages to escape some time later, only to end up killed by Kraven the Hunter, who displays it as a trophy titled Piranha inside his Loft, alongside the other cross-species.