This will be easier for everyone if you remain calm... and do as I say.
~ Martin Li to Mary Jane Watson before his takeover of Grand Central Station.
Beat the demon? I AM the Demon!
~ Mister Negative to Spider-Man.
Mister Negative (real name: Martin Li) is the central antagonist of Marvel's Spider-Man and a mentioned antagonist in its spin-off Marvel's Spider-Man: Miles Morales.
He is the director of F.E.A.S.T., the secret leader of the Inner Demons, and the second-in-command of the Sinister Six who intends to use terrorism as a means to expose Norman Osborn for his criminal activities and avenge his long-deceased parents.
Martin Li was born in 1978 in Dali, China, to the late Mr. and Mrs. Li. As a child, Martin Li developed an undetermined medical condition and was taken to Oscorp by his parents where they later perished at his hands after Norman Osborn injected him with an experimental GR-27 serum that caused him to become Mister Negative.
Marvel's Spider-Man (2018)
Martin Li is the director of the assistance shelter F.E.A.S.T. and has an outgoing connection and outreach with the homeless who attend the F.E.A.S.T. building. Secretly, he is the ruthless leader of the Inner Demons, who has the ability to harness, transfer and emit negative energy, following an experiment gone awry at Oscorp. Li blames Mayor Norman Osborn for the deaths of his parents, and begins terrorizing the city.
Following his defeat, he becomes second-in-command of the Sinister Six, organized by Doctor Octopus. In the story's climax, Mister Negative is defeated by Spider-Man a second time, and then thrown into a wall by Octavius for his failure, knocking him out cold. A Daily Bugle newspaper mentions that after his second defeat, Li is revealed to still be at large, having regained consciousness and escaped into hiding, with the Inner Demons still at large. He was eventually recaptured by authorities and thrown back into the Raft, most likely either between after the main story and before the DLC episode trilogy The City that Never Sleeps, during the latter, or sometime after.
Marvel's Spider-Man: Miles Morales (2020)
More than a year after the defeat of Doctor Octopus and the Sinister six, Martin is nowhere to be seen or heard from during Tinkerer's campaign against Simon Krieger. In this time, Miles Morales, Peter Parker's superhero apprentice has taken over his role as the sole Spider-Man in New York City while Peter goes to Symkaria with Mary Jane.
Martin is mentioned and alluded throughout the story. It's mentioned that the Inner Demons disbanded following a fight with the Underground sometime after his second arrest. He is also mentioned by Rio Morales, Miles' mother, as the one who killed her husband Jefferson Davis, which in turn inspired her to start her own political campaign for councilwoman of New York City. He is also indirectly mentioned by Aaron Davis, Miles' uncle, as the cause for which his brother died, leading him to try to imprison Miles to protect him and not lose him like Jefferson.
Powers and Abilities
Dark Energy Manipulation: Due to being exposed to an untested variant of the Devil's Breath, which combined with his mysterious illness, gave him the power to generate and manipulate large amounts of negative energy. This allows him to summon weapons including swords.
Superhuman Abilities: As a side effect of his powers, he has superhuman levels of strength, speed, durability, and stamina. He can take direct hits from Spider-Man and even overpower Spider-Man physically. He can move in small dashes of speed, akin to teleportation.
Power Bestowal: Li has the ability to transfer portions of his energy to other people and "corrupt" them. Not only does this give him control over their minds, but it also bestows those infected with powers of their own. Li can absorb the energy he has given away should he need to increase his own strength.
Energy Constructs: Li can create powerful energy constructs to aid him in a fight.
Historical Expert: He has a degree in art history as well as arcane lore.
Business Skills: He was able to make a vast fortune in the shipping industry in China, before moving back to New York City. He was also able to establish F.E.A.S.T centers around them and property manage their resources and capabilities.
Philanthropy: Li has known to possess inspiring altruistic philanthropic philosophies. His genuine dedication to F.E.A.S.T can be seen by the fact that he chooses to help out at the F.E.A.S.T centers personally, despite him having the financial resources to hire more workers.
Communication: Li is great at speaking in front of audiences as shown throughout several scenes throughout the game. Being a business man, he is also good at communicating with his employees and partners.
Martin in a helicopter.
Martin Li after telling Osborn to come to grand central station.
Mister Negative attacks Spider-Man in the subway train.
The Sinister Six preparing to fight Spider-Man at the Raft.
As shown in the spin-off, Mister Negative's actions deeply impacted Miles Morales' family: it was because of Jefferson Davis' death, which he caused, that Jefferson's wife Rio started to run for councilwoman and it was also because of losing Jefferson that Aaron Davis, his brother, decided to do whatever he needed to protect his nephew at all costs to not lose him too.