Odieus's Quest for the Magic Flingshot, by Anonymous (1990)
(2 ratings)

On Your Back, by Dan Doyle III (2013)
(2 ratings)

One Game in Search of a Story, by NOM3RCY (2010)
(2 ratings)

One Room Adventure by Jorge Mir 1983 (2 ratings)

Open Sorcery by Abigail Corfman 2016 (55 ratings)

Operation Crab Key, by Joe Vercellone (1984)
(2 ratings)

Orc Slayer by Warren Speed 1984

Out of the Limelight, by Jonathan Scott and Stephen Boyd (1992)

The Prism of Shadows, by Wade Clarke and James Anderson (2009)
(1 rating)

Project Nova, by Mark Cantrell (1987)

The Purple Island Glow-Grubs by Dave Strand and Kelly Levy 2015 (1 rating)

Quest by Roger Chaffee 1978 (1 rating)

Quest for the Fire Dragon, by John Nelson and Frank Kunze (2004)
(3 ratings)

Quest for the Holy Grail, by Evan Hodson (1983)
(3 ratings)

Quest for the Serpent's Eye by Lazygamedesigner82 2020 (1 rating)

Quest room: Hanon by Burrik 2018 (1 rating)

Questor's Quest by Mark Stahl 2015 (6 ratings)

Rebel Planet by Stefan Ufnowski 1986 (4 ratings)

Red Radish Robotics by Gibbo 2020 (9 ratings)

The Reliques of Tolti-Aph by Graham Nelson 2006 (14 ratings)