tips for fastest ending

[Vilk]

Originally Posted by DGDobrev

I doubt it can be done in 5 days. 6... not sure.

These are the areas you must travel to and lose time (even if you time it properly, you still need to travel):
You lose 1 day from turtle island back to greenwort.
...

You start day 1 12AM so in fact when you are back from turtle island it's already day 2 7AM+, impossible to do better. So the path you describe is a 7 days path.

As far I know only two players that post their records here did it in 7 days in impossible, Calinda with a warrior and Crepuscule with a mage (and one less quest done).

Both are quite amazing score, only Calinda provides/provided feedback and savegame.