On Reflection, by Lee Tonks (2007)

Onaar by Robert DeFord 2015 (10 ratings)

Open Sorcery: Sea++ by Abigail Corfman 2021 (1 rating)

Operation Aquatrash, by Heaven Aeroplane, Equator, IcE, Art Wizard (1997)

Orb of My Life, by John Nelson (1986)
(1 rating)

Passenger, by Niall Richard Murphy (2004)
(1 rating)

The Peccary Myth by Gerardo Aerssens (as Pergola Cavendish) 2014 (4 ratings)

Pentari: The Apprentice by Howard Sherman 2007

Perilous Magic, by David Fillmore (1999)
(8 ratings)

Portcullis by Robin Johnson 2016 (13 ratings)

Portrait of a Troubled Artist, by Joel Marler (2017)

Punkirita Quest 1: Liquid, by Ryan Stevens (1996)
(3 ratings)

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

The Quest for Trezore, by Jim Jacobson (1980)
(1 rating)

Race For Midnight by Steven Sacks 1981

Rance the Dungeonkeeper, by Jan Åberg (1986)
(1 rating)

Realistic Zork, by lempamo (2016)

Return to Camelot, by Finn Rosenløv (2011)
(9 ratings)

Return to Zork: Another Story, by Stefano Canali (2000)
(3 ratings)

Revenge of the Thing-Fish, by Jan Åberg (1986)
(1 rating)