Highly replayable games

I was hoping to find more games that were highly replayable. Here is my definition for one:

A game that is always enjoyable to go back and play no matter what mood. These games don't force you to replay them for the sake of completing everything 100% or because improving a character or one's skills. You must want to replay it just for the fun and joy that can only be experienced through the gaming medium.

I'll list some of my own: Spelunky, Noitu Love 2, Nikujin, Team Fortress 2.

Half Life 2 + Episodes and KoTOR I/II. I've completed all these games several times and I still go back to 'em.

The Sims 3. biggest_loser

To me, I can never stop playing this game. Always would jump into it to keep my family progressing.

Half Life 2 + Episodes and KoTOR I/II. I've completed all these games several times and I still go back to 'em.

dinuattila

Yeah, definately KOTOR, and also Vice City, when you just feel like killing something/someone etc.

The Elder Scrolls games with or without mods. Only singleplayer games I own that I've played through more than once.

Mass Effect and Sins of a Solar Empire.

BioWare games, Team Fortress 2, Total War games, Civilization 4, Diablo 2, Battlefield games, Morrowind/Oblvion, Fallout series, Sims series

Total War, The Sims, SimCity4, Morrowind (with mods ofc), Vice City, any online FPS with a big fanbase (ie CS, COD, TF)

total war games, Cossacks.

Heroes of Might and Magic 2, Doom II, Shock 2, Diablo 2, HeXen, Mount & Blade and Team Fortress 2.

Mass Effect, Stalker: Shadow of Chernobyl, and Crysis are the only ones i can think of that i replay regularly

StarCraft.