diablo-3
I just disconnected and my quest seems to have been reset to a few minutes before where I currently was. However, it seems like I kept everything in my inventory that I found in meantime.
When exactly is the game automatically saved? And what kind of stuff usually goes lost when something happens without the game having saved?
Also, is there some way to save manually? Is the game saved when I log out?
UPDATED:
Legendaries can drop at any time, anywhere, albeit rarely. With the Loot 2.0 updates, new heroes from lvl 1-59 will get a guaranteed legendary drop for the first kill of The Butcher, Belial, Azmodan and Diablo.
Characters below level 11 are unlikely to find Legendary items, because they have a minimum level requirement. Currently there are no Legendary items available below level 11. (source)
For level 60 characters, you should get a guaranteed legendary drop from Diablo every time you kill him after resetting all of your quests and working your way back to him.
Higher tiers of Torment supposedly include an increase in legendary drop rates, but the exact amount of the bonus has not been disclosed. It doesn't seem to be major, though, so you should pick a lower tier of Torment over a higher one if you will kill significantly faster in the lower tier.
Note, however, that some legendaries will only drop in Torment I - VI.
Original answer:
Yes, there are set and legendary items.
Many of them will be available through crafting, requiring the recipe to drop.
Others will drop randomly, but extremely rarely. This can happen at any level, as not all legendaries are high level gear.
The best legendaries will be Inferno drops.
However, it has been stated that the very best items in the game will not be the set items or legendaries. Instead, the very best will be Inferno level randomly-generated rares.
Best Answer
In terms of your inventory and such, there is no such thing as the game "saving", updates are instantly applied to the server, so it isn't possible to lose anything. In terms of quests, there are frequent "checkpoints" throughout the game (usually about every 5-10 minutes). Anytime you stop playing, you will resume the quest from your last checkpoint the next time you start again. There is no way to force a quest save other than reaching one of these points.