https://www.gamespot.com/articles/first-overwatch-halloween-terror-2018-skin-reveale/1100-6462250/

Blizzard has announced the first new Overwatch Legendary skin that players will be able to earn in 2018's Halloween Terror event. This year, Doomfist is getting a new holiday-themed skin that transforms him into a Swamp Monster.

The new Legendary skin gives Doomfist a scaly blue complexion, as well as gills and horned fins. The skin honestly makes Doomfist look more like the Amphibian Man from The Shape of Water than the swamp monsters seen in other stories like Goosebumps and Scooby-Doo. Doomfist's Legendary Swamp Monster skin won't be available until Halloween Terror starts, and you'll no longer be able to unlock it once Halloween ends.