DOOM engine (10)

DOOM

Also known as Doom: Evil Unleashed

First-Person Shooter, 1993
Shareware (installed), Shareware

DOOM II

Also known as DOOM II: Hell on Earth

First-Person Shooter, 1994

HACX

Also known as HACX - Twitch 'n Kill

First-Person Shooter, 1997
Full version, Full version (installed)

Hell to Pay

Also known as Hell to Pay, Limited Edition

Expansion Set, 1996
Playable demo

Heretic

First-Person Shooter, 1994
Shareware (installed), Shareware

Hexen: Beyond Heretic

Also known as Heretic 2

Adventure, 1995
Playable demo, Preview, FAQ

Perdition's Gate

Also known as Perdition's Gate: Limited Edition

Expansion Set, 1996
Playable demo

REKKR

First-Person Shooter, 2018
Freeware (installed), Freeware, Freeware

Strife

Also known as Strife: Trust No One, Strife: Quest for the Sigil

Role-Playing, 1996
Playable demo (installed), Playable demo