Play abandonware games
Technically, abandonware games are games not supported anymore from their developers. If the original developer company is no more and if the game is so old that no one cares for it anymore, it becomes "abandoned". Usually, no one bothers about abandoned games but the retro gaming community, that's why it's so easy to find online games developed for now defuct platforms like Commodore 64, MS DOS, Sega Genesis, Windows 3.1, Spectrum, Amstrad CPC, etc. There were so many different home computers and consoles in the 80s and the 90s that abandonware became a niche phenomenon. If you're into abandonware for DOS and Windows, take a look at Abandonware DOS.
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Strip Poker Deluxe
card game / strip poker
Eagle Rock Enterprises

Strip Poker 3
card game / strip poker
Artworx Software

Cover Girl Strip Poker
card game / strip poker
Emotional Pictures

Strip Poker Professional
card game / strip poker
Artworx Software

Strip Poker 2
card game / strip poker
Artworx Software

Railroad Tycoon
simulation / management
MicroProse Software

Dreamweb
adventure / point & click
Creative Reality

Strip Poker: a Sizzling Game of Chance
card game / strip poker
Artworx Software

Mario Bros VGA
platformer / arcade
Dave Sharpless

The Three Stooges
action
Cinemaware

Interactive Girls Club Games
puzzle
Interactive Girls Club

Captain Comic 2: Fractured Reality
platformer / metroidvania
Michael A. Denio

Mario and Luigi
platformer / arcade
Mike Wiering

TV Sports: Basketball
action
Cinemaware

TV Sports: Boxing
action
Cinemaware

The Adventures of Captain Comic
platformer / metroidvania
Michael A. Denio

It Came from the Desert
adventure / action-adventure
Cinemaware

ZZT
action / action puzzle
Epic MegaGames

The Lost Vikings
platformer / action puzzle
Interplay Productions

Sinbad and the Throne of the Falcon
action / action-adventure
Cinemaware

Genocide
strategy / artillery
PyroSoft
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