| Title |
Publisher |
Year |
Language |
Documents |
| Obituario |
Santiago Eximeno |
2002 |
Spanish |
|
| Observatoire, L' |
Stéphane F  |
2016 |
French |
|
| Ocaso Mortal |
Dhan |
2001 |
Spanish |
|
| Ocean Beach |
James Banks |
2019 |
English |
|
| Odieus' Quest for the Magic Flingshot |
CTH Enterprises , Grim Reaper, The  |
1988 |
English |
Solution |
| Of Forms Unknown |
Chris Markwyn |
1996 |
English |
|
| Of Their Shadows Deep |
Amanda Walker |
2022 |
English |
Solution |
| Offensive Probing |
Benjamin Richard "Yahtzee" Croshaw  |
1999 |
English |
Solution |
| Office Goose |
Liz Henry |
2019 |
English |
|
| Ofrenda a la Pincoya |
Sebastian Armas  |
2008 |
Spanish |
|
| Oily Deeps, The |
John Cater |
1999 |
English |
Solution, Map |
| Old Fogey |
Simon Deimel |
2015 |
English |
|
| Old Jim's Convenience Store |
Anssi Räisänen |
2019 |
English |
|
| Old King Nebb |
Caleb Canby Wilson |
2020 |
English |
|
| Old Sherwood Cemetary, The |
Duchess |
2002 |
English |
Solution, Map |
| Olivia's Orphanorium |
Sam Kabo Ashwell |
2012 |
English |
|
| Ollie Ollie Oxen Free |
Carolyn VanEseltine |
2013 |
English |
|
| Olvido Mortal |
Andrés Viedma Peláez |
2000 |
Spanish |
|
| OMNIQuest |
Chris Barden, Chris Ethridge |
1988 |
English |
Map, Hints |
| On Optimism |
Zach Flynn  |
2005 |
English |
Solution |
| Once in a Lifetime Opportunity, A |
Elias Ramsberg |
2021 |
English |
Solution, Map |
| One About the Chicken, the Lion and the Monkey?, The |
Sam Barlow |
1998 |
English |
|
| One Eye Open |
Carolyn VanEseltine, Colin Sandel |
2010 |
English |
|
| One Fish, Two Fish, Red Fish |
David Marques |
2021 |
English |
|
| One Girl |
Dr Khel |
2001 |
English |
Solution |
| One King to Loot them All |
Onno Brouwer |
2023 |
English |
|
| One Night in the North Atlantic |
Christopher Huang |
1999 |
English |
Solution, Map |
| One Way Out |
Steffen Görzig |
2017 |
English |
|
| Onirische Garten, Der |
Dara |
2018 |
German |
|
| Only After Dark |
Gunther Schmidl |
1999 |
English |
Solution, Map |
| OnNoEf |
Evin Robertson |
1999 |
English |
Solution, Map |
| Opening Night |
David Batterham |
2008 |
English |
|
| Oppositely Opal |
Buster Hudson |
2015 |
English |
|
| Order |
John Evans |
2004 |
English |
|
| Orevore Courier |
Brian Rapp |
2007 |
English |
|
| Orfeo en los Infiernos |
Xavi Carrascosa  |
1997 |
Spanish |
|
| Origin of Madame Time, The |
Brian Rushton  |
2018 |
English |
|
| Origins |
Ade McT |
2016 |
English |
|
| Orion Agenda, The |
Ryan Weisenberger |
2004 |
English |
|
| Orpington |
William J. Shlaer |
1998 |
English |
|
| Oth. |
Gunther Schmidl |
2002 |
English |
Solution, Map |
| Otras Palabras, En |
Aryekaix |
2003 |
Spanish |
|
| Out |
Viktor Sobol |
2019 |
English |
|
| Out Of Line |
Cody Gaisser |
2022 |
English |
|
| Outcasts, The |
Dmitry Ivanushko |
2017 |
English |
|
| Outsided |
Chad Elliott |
1999 |
English |
Solution |
| Owl Consults, The |
Cidney Hamilton, Nick Mathewson, Thomas Mack |
2017 |
English |
|
| Oxygen |
Hansi Berlin |
2015 |
English |
|
| Oxygen |
Benjamin Sokal |
2010 |
English |
Solution |