Most amount of sheer, unstoppable, replayable fun in a single player game

[Otaku13]

wow i have to many games that fit this category. Pokemon, Minecraft, Dawn of War, Sins of a solar empire, the original three spyro the dragon games, The Rachet and Clank games, Okami, DMC 3, Freespace 2, Digimon World. Ico, Psychonauts, Warcraft 3 (singleplayer) Starcraft (single player) Diablo 2. Advance Wars, Fire Emblem, Metroid Prime. Baldurs Gate.

 

[The Unworthy Gentleman]

Minecraft, definitely. Multiplayer is fun and everything, but you can always go into your own little world and fend off creepers. And then look up from your computer and realize it's six in the morning.

I'm going to have to go with this one. The game is just amazing to play, you have so many options on what to build and with the new dyes for wool you have even more to build without needing to re-texture the game. I often find myself in my own little world. Sometimes I'll be ice fishing, sometimes I'll be hunting pigs, occasionally I'll have sacrificial ceremonies where I burn a cow for the Creeper God, or the snow God. Man I wish we had snow. Rain would also be something I want. God, I jus

 

[Faultline]

I can't believe I joined the forum just to reply to this thread but...

Suikoden 2 on psx! I loved that game because it had everything: a compelling storyline, almost endless possibilities that changed as the game progressed, a decent combat system that sometimes became a turn-based strategy game and 108 different characters all with a unique identity (well, except soldier-guy133, but that's not the point!). Overall it was an experience that set the bar for me and for games in general. And pokémon + prototype. Collecting minions and killing an entire city respectively, I spent hours on those with pride.

 

[Bender Rodriguez]

This might seem like an odd one but...
Mafia 2

I guess its just me who loves modding classic cars, jumping and shooting accompanied by a brilliant 50s soundtrack.