Thief (series)/YMMV

Concerning the game trilogy as a whole

 * Alternative Character Interpretation : Does Garrett keep helping others and saving the world because he's a Knight in Sour Armour, or is he just a pragmatic egoist?
 * Complete Monster : While the villains in the first two games have the destruction of life as we know it as their main goal, they seem to possess a Humans Are the Real Monsters mentality going on to justify their actions. The Big Bad of the third game personally murders children to wear their skin and maintain her immortality.
 * Ensemble Darkhorse: The two guards that keep showing up to guard different places and people throughout the first game, providing a number of memorable conversations (most notably the "bear pits" conversation from the first mission.)
 * Fetish Retardant :
 * Then again, when she and Garrett meet again in Thief II : The Metal Age...
 * Game Breaker / Lord British Postulate : The last part of the third game has you sneaking past the Big Bad several times to set in place various items. She is 100% invincible... but enough oil flasks WILL make her slip, fall, and become unconscious. Oops!
 * Even better, do this at the docks and you can make her fall into the ocean.
 * Hell Is That Noise: In The Maw, the chattering, lip smacking, mewling and whining by the... creatures in the level. Completely alien, and extremely unsettling.
 * Most of the scary environments in the series, really. The bizarre ambiance of the Cradle makes the Maw feel downright comfortable.
 * The golems in the third game, especially when they find you. CRUSH AND KILL AND CRUSH AND KILL AND SMASH AND KILL AND SMASH...!!!
 * Nightmare Fuel: The Haunted Cathedral (Thief 2) and the Shalebridge Cradle (Deadly Shadows) have been touted as two of the scariest levels in non-horror games. Both created an uncomfortable and unexpected atmosphere that left us dreading the necessity of going though that door...
 * Porting Disaster: Despite claiming otherwise on the box, updated rereleases of the series from as recent as 2009 occasionally crash due to problems reading the information from multi-core processors. Or, in layman's terms, if you've got at least an above-average PC, YOU'RE SCREWED.
 * There are of course ways around this by restricting the threading of the application so it only uses one core of a processor, and it is not very complicated to achieve using the Windows task manager, but it is still a bit of an annoyance that a user has to do that.
 * It takes a bit of fiddling around but there are plenty of tutorials and instructions to set the game working on mordern computers on the Through the Looking Glass forums.
 * As of now, the version released on GOG.com seems to be stable, as does the Steam release.

Fan missions, mods and other fan works

 * Fan Wank : Since the storylines of many fan missions often extrapolate from established Thief canon, you're bound to bump into something based on WMG by the series' fans.
 * It's Short, So It Sucks: The number one complaint about any fan-mission is "I wish it were longer!" Not to say that FMs are bad or short (many of them rival the original missions in length and complexity), but since most FMs are single-level, the fun can only last so long.
 * They Changed It, Now It Sucks: Completely averted; almost any change to the status quo is seen as a brilliant innovation, especially when pulled off right.