Games like Biotoxin: The Dark Days
Games like Biotoxin: The Dark Days include Hotline Miami, CARRION, Hotline Miami 2: Wrong Number, Blasphemous, and MO:Astray. We matched them by the tags players give Biotoxin: The Dark Days on Steam (Action, Adventure, Indie, Gore, and Violent): closest matches first, and among equally close ones the better-known games.

Hotline Miami
Shared: Action · Indie · Violent

CARRION
Shared: Gore · Action · Pixel Graphics

Hotline Miami 2: Wrong Number
Shared: Gore · Action · Violent

Blasphemous
Shared: Gore · Pixel Graphics · Indie

MO:Astray
Shared: Action · Indie · Adventure

Kindergarten 2
Shared: Adventure · Gore · Indie

Katana ZERO
Shared: Action · Pixel Graphics · Indie

My Friend Pedro
Shared: Action · Indie · Gore

Broforce
Shared: Action · Pixel Graphics · Indie

Paint the Town Red
Shared: Action · Gore · Violent

Serious Sam 4
Shared: Action · Gore · Adventure

Party Hard
Shared: Pixel Graphics · Indie · Action

NOT A HERO
Shared: Action · Indie · Adventure

SANABI
Shared: Action · Pixel Graphics · Adventure

Prodeus
Shared: Action · Gore · Indie

DOOM Eternal
Shared: Action · Gore · Violent

People Playground
Shared: Gore · Violent · Pixel Graphics

Middle-earth: Shadow of War
Shared: Action · Adventure · Violent

DOKA 2 KISHKI EDITION
Shared: Action · Gore · Violent

Mother Russia Bleeds
Shared: Action · Gore · Violent

BUTCHER
Shared: Action · Indie · Gore

Skul: The Hero Slayer
Shared: Action · Indie · Pixel Graphics

Party Hard 2
Shared: Indie · Action · Violent

Devolver Bootleg
Shared: Action · Indie · Adventure