According to @Erile post here: tested by myself, i wear no items (no weapon or armor)... and the quest "birthday suit pub crawl" unlocked without any problem for me.
Halfway Through unlocks incorrectly. I finished 1.3 and went back to 1.1 to do some grinding and it gave me the finish Act 1 quest when I haven't even tried 1.4.
The quests here are pretty variable in terms of difficulty.
For anyone who is like me and has beaten the game already with sorceress, the barrels is best done on 1.2(21 barrels a pass on easy mode ofc), and the whirling combo is best done on map 1(there's 2 orcs near the end, you'll have to do a minimum of 10 dmg per strike). It feels like picking warrior will take you a bit longer to do the quests(chicken requires at least lvl 10-12). It's also kind of amusing how the epic items quest was a downgrade from my mixed legend(wand+book) and epic build.
@Ferret@IriySoft What @Gantic said about the "Halfway Through" Quest is correct unfortunately. I too went back to Act 1.1 after completing Act 1.3 to grind for money and after finishing that, said Quest was awarded to me so there must be a glitch somewhere during the unlocking.
Also, the "Epic" Quest, where one has to wear Epic Armor and Weapons only, is less difficult than 'Hard' in my opinion... I managed to buy several epic armor pieces by grinding money and buying them from the trader. I got the last missing piece of epic armor and an epic weapon from a barrel and a treasure chest, thus completing the epic set. maybe 'Medium' is a better label for this Quest?
Otherwise, awesome game guys! I'm loving this to the death!! Yeah!! Oh... wait... no... I actually need to stay alive if I want to slay all those enemies! Heh...
@Andelhofs use the warriors skill... you just need 2 feat points to do so.
They are several places with two enemys close enough to perform it, 1-1 [3] is the easiest one, just before the last enemy you have two placed close enough so you can hit them with one circular strike... all you need is enough dmg^^