Games similar to Afterfall InSanity include Doom. It's paid, but Zandronum is free. Other options are Shadow Warrior (Reboot), Prodeus, Dead Space and DUSK. In total there are seven First-Person Shooters like Afterfall InSanity for Windows, Mac and Linux.
Doom is a science fiction horror-themed first-person shooter video game in which players assume the role of a space marine, popularly known as "Doomguy", who must fight his way through the hordes of invading demons from Hell.
United States
Shadow Warrior is a series of first-person shooter video games that focuses on the exploits of Lo Wang, a modern ninja warrior who fights through hordes of demons.
Poland
EU
Prodeus is a first-person shooter of old, re-imagined using modern rendering techniques and technology. Experience the quality you’d expect from a modern AAA game, designed with retro aesthetics and gameplay that invoke the tech-imposed limits of older hardware.
Canada
Dead Space is a survival horror third-person shooter video game for Microsoft Windows, PlayStation 3 and Xbox 360.
United States
Battle through an onslaught of mystical backwater cultists, possessed militants & even darker forces as you attempt to discover just what lurks beneath the Earth in this retro FPS inspired by the '90s legends.
United States
Zandronum is a multiplayer oriented port, based off Skulltag, for Doom and Doom II by id Software.
Wrack: Exoverse is the follow-up to the 2014 first-person shooter Wrack. It was a very fast-paced, arcade-style game with heavy influences from classic shooters like Doom and Quake.
United States
