*Human mutate (formerly)
|First appearance||"Return to the Spider-Verse - Part 3"|
|Voiced by||Keone Young|
Martin Li is a former member of Hammerhead's gang. Martin betrays Hammerhead after the former is exasperated for the latter misusing a shard of the Siege Perilous to power up his weaponry in a gang war against Joe Fixit. After touching the shard of the Siege Perilous, he becomes "Mister Negative", gaining the ability transmutate anything he touches into stone. After being defeated by Spider-Man, Spider-Man Noir, and Mr. Fixit, Martin is stripped of his powers and reverted back to his human form.