Owned but not played.

1. The WitcherThe Witcherhttps://giantbomb.com/wiki/Games/The_WitcherOpens wiki page

2. Dead SpaceDead Spacehttps://giantbomb.com/wiki/Games/Dead_SpaceOpens wiki page

3. Half-Life 2: Episode OneHalf-Life 2: Episode Onehttps://giantbomb.com/wiki/Games/Half_Life_2_Episode_OneOpens wiki page

Unfinished prequel. Update: UNTIL NOW, good grief was it not worth the wait.

4. Half-Life 2: Episode TwoHalf-Life 2: Episode Twohttps://giantbomb.com/wiki/Games/Half_Life_2_Episode_TwoOpens wiki page

unfinished prequel (check the list)

5. Titan QuestTitan Questhttps://giantbomb.com/wiki/Games/Titan_QuestOpens wiki page

6. Tales of Monkey Island Chapter 1: Launch of the Screaming NarwhalTales of Monkey Island Chapter 1: Launch of the Screaming Narwhalhttps://giantbomb.com/wiki/Games/Tales_of_Monkey_Island_Chapter_1_Launch_of_the_Screaming_NarwhalOpens wiki page

7. Left 4 Dead 2Left 4 Dead 2https://giantbomb.com/wiki/Games/Left_4_Dead_2Opens wiki page

8. Orcs Must Die!Orcs Must Die!https://giantbomb.com/wiki/Games/Orcs_Must_DieOpens wiki page

9. Star Wars: Knights of the Old RepublicStar Wars: Knights of the Old Republichttps://giantbomb.com/wiki/Games/Star_Wars_Knights_of_the_Old_RepublicOpens wiki page

10. Lara Croft Tomb Raider: LegendLara Croft Tomb Raider: Legendhttps://giantbomb.com/wiki/Games/Lara_Croft_Tomb_Raider_LegendOpens wiki page

Eidos Bundle in Steam sale which included Batman Arkham.