challenge conditions:
dont wear any armor except night vision helmet (clothing only)
dont use shields
dont separate groups of enemies
dont run from fights to restore stamina
Also, since there is no any ending i have set several goals:
get to the portal
loot all healing salves (so i can't skip bosses on lvl 2, catacombs and lvl 3)
kill everyone on the way
music from Stronghold (ost)