| Title | Publisher | Year | Language | Documents |
|---|---|---|---|---|
| Caffeination | Michael Loegering | 2003 | English | Solution |
| Canapés of Death, The | Cedric V. F. Knight | 2003 | English | Solution, Map |
| Casa del Olvido, La | Xavi Carrascosa |
2003 | Spanish | |
| Caso del Misterioso Asesinato del Domador de Pulgas del Circo de Montmartre, El | Jarel |
2003 | Spanish | |
| Castillo de los Lamentos, El | Sebastián Balestrieri | 2003 | Spanish | |
| Cave of Adventure | Stephen Granade | 2003 | English | |
| Caverns of Doom | Iain Merrick | 2003 | English | |
| Cerulean Stowaway | Roger Descheneaux | 2003 | English | |
| Cheating Death | Adam Biltcliffe | 2003 | English | Solution, Map |
| Cheer Up | Sam Thursfield | 2003 | English | Solution, Map |
| City of Secrets | Emily Short | 2003 | English | Solution |
| Cloak of Ultimate Darkness | Iain Merrick | 2003 | English | |
| Cough Cough | Jennifer Maddox | 2003 | English | Solution, Map |
| Crazy Christmas | Christoph Winkler | 2003 | German | |
| Cross of Fire, The | Matthew Carey | 2003 | English | Solution |
| Cubo | Santiago Eximeno | 2003 | Spanish | |
| Curse of Manorland | James King | 2003 | English | Solution |