The Best Non-Linear RPGs, IMHO

  1. The Elder Scrolls IV: Oblivion - Assume the role of a prisoner who receives a Get Out of Jail Free Card directly from the Emperor of the lands. After you're free, you can do the main quest, or do a hundred thousand other things in this gorgeous, lavishly painted world, everything from buying a home and installing furniture to raiding ancient tombs and finding powerful artifacts.
  2. The Elder Scrolls III: Morrowind - Again, an earlier Bethesda game with blockier graphics but a larger world, you are a prisoner who is given a chance for life by joining the Emperor's secret bodyguard faction, the Blades. Warning: this world is huge, lined with craggy high mountains, monstrous temples, and random travelers looking for help. Dozens of factions to join and move up the ranks, totally outside the main quest, which if combined with the Bloodmoon and Tribunal expansion packs, gives you over 200 whopping hours of quest time, outside of extra stuff you find to do.
  3. Neverwinter Nights - Create your own character, take part in a huge story filled with hundreds of sidequests, develop your own modules and download custom player written ones. There are so many character classes which all provide different playing styles, and so many different modules to download (most player written modules are anywhere from 3-20 hours to complete), you are left with literally the power to explore anything. The sidequests in the main campaign, however, remain the only non-linear aspect of this game, but there are enough of those to stock a library.
  4. Baldur's Gate - The original, and as I haven't played through BGII fully yet, still my favorite. Adventure along Faerun's western Sword Coast, explore colorfully painted environments and take part in scores of well-developed, huge quests.
  5. Baldur's Gate II: Shadows of Amn/Throne of Bhaal - Even more quests to complete, through your actions you can also increase the amount of friendship between your main character and the various characters in your group, including even having a child with one. Reputedly (though I haven't done this) you can spend upwards to two weeks straight just playing quests from a particular city, and that's outside of quests you can complete elsewhere.
  6. Planescape: Torment - The last great hand-drawn Black Isles RPG (before they went under), this extremely literary game is said to contain over 1,000,000 words of text. Novels contain anywhere from 50,000-250,000 (250k is about 850 pages) words, which lends this nice, little game to have at least four huge novels of story and dialogue, just within the borders of its 1.5 gigabyte storage space.
  7. Sacred: Underworld - To put it simply, after spending about three hours of constant exploration, either on foot or flying (which is quicker), I was only able to explore about 2.5% more of the world. I didn't fight any of the hundreds of monsters I encountered, and never went to the same place twice. The map goes on and on, dotted with secret caves, treasure troves, hordes of coins guarded by dragons and even worse things, and combined with a sidequest system of 300 quests, that's an *incredible* amount of game. The main plotline, is of course, optional (in this case!). With Underworld (the expansion), the world is increased by at least 50% (though I don't know exacts).
  8. The Ur-Quan Masters - Not quite an RPG, but it does contain some elements (role-playing, ship upgrading, and exploration), but even so this gigantic world -er... universe, contains so many places to go and see, it's boggling, if not a bit intimidating. The main plotline seems simple enough, but you'll probably get sucked into the vast empty spaces of unexplored space, discover weird new races, crazy plotlines, and fascinating, alien planets.
  9. Fallout 2 - I didn't include the original Fallout, because it's timed. Fallout 2 isn't, which gives it an opportunity to be truly non-linear. Similar to the Baldur's Gate games, except this is post-apocalyptic/sort of futuristic. You start out as a guy with a spear whose job is to save the world (yeah...), but like the previous Fallout game, the story turns into so much more. There's a ton to do though, and multiple endings depending on what quests/sidequests you complete or how well you complete them.
  10. Avernum - Huge world, a step above roguelikes (those funny old geeked RPGs where you are a "@" and you walk around ASCII text fields and kill things) in that it has graphics. Be prepared for this one (or any of the series), as quests are not "marked" per say, in any sort of journal (you can, however, write them in your journal, which is recommended). You have to remember them in yes, your *own* head (as it should be). That withstanding, the 80 (or so) sidequests offer a lot of extra exploration, but generally are just fetch quests, with some being more extensive. The world is bloody huge, again which makes this a nice place to walk around in and see the wonders you can do with really simple artwork, and let your imagination fly.
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From the best (1) to... well, not the best (10), but still dang good.

Note: These are all PC games (not console, as console developers outside of Bethesda, typically don't develop non-linear RPGs). They are not pen and paper RPGs, for the record.