Games like illWill
Games like illWill include CULTIC, DUSK, Warhammer 40,000: Boltgun, ULTRAKILL, and HROT. We matched them by the tags players give illWill on Steam (Boomer Shooter, FPS, Spectacle fighter, Psychedelic, and Shooter): closest matches first, and among equally close ones the better-known games.

CULTIC
Shared: Boomer Shooter · FPS · Shooter

DUSK
Shared: Boomer Shooter · FPS · Shooter

Warhammer 40,000: Boltgun
Shared: Boomer Shooter · FPS · Shooter

ULTRAKILL
Shared: FPS · Boomer Shooter · Spectacle fighter

HROT
Shared: FPS · Boomer Shooter · Shooter

SharpShooter3D
Shared: Boomer Shooter · FPS · First-Person

Forgive Me Father
Shared: Boomer Shooter · FPS · Shooter

DOOM + DOOM II
Shared: FPS · Boomer Shooter · Action

AMID EVIL
Shared: Boomer Shooter · FPS · Shooter

MOUSE: P.I. For Hire
Shared: FPS · Boomer Shooter · Action

Quake
Shared: FPS · Shooter · Action

Counter-Strike
Shared: FPS · Action · Shooter

DOOM 64
Shared: FPS · Action · Boomer Shooter

Apex Legends™
Shared: FPS · Shooter · First-Person

Serious Sam: Siberian Mayhem
Shared: Boomer Shooter · Shooter · Action

Paladins®
Shared: FPS · Shooter · Action

BRAZILIAN DRUG DEALER 3: I OPENED A PORTAL TO HELL IN THE FAVELA TRYING TO REVIVE MIT AIA I NEED TO CLOSE IT
Shared: Boomer Shooter · FPS · Shooter

Quake II
Shared: FPS · Boomer Shooter · Shooter

420BLAZEIT 2: GAME OF THE YEAR -=Dank Dreams and Goated Memes=- [#wow/11 Like and Subscribe] Poggerz Edition
Shared: Boomer Shooter · FPS · Shooter

Half-Life
Shared: FPS · Shooter · 1990's

Post Void
Shared: FPS · Psychedelic · Shooter

Call of Duty®
Shared: FPS · Shooter · Action

Prodeus
Shared: Boomer Shooter · FPS · Shooter

DOOM
Shared: FPS · Shooter · Action