Superbosses, very dangerous and wealthy monsters. They all have some things in common - they drop quest items, they drop gem scrolls, each of them has a forte and a weakness. They occupy levels, which are not often visited, places, you don't need to enter to complete the game. Let's take a look at them...
Act I
Troubleshooter
Location: Hole Level 2
Boss scroll: Yes (Hell)
Forte: Poison
Weakness: Magic
Dark Fighter
Location: Pit Level 2
Boss scroll: Yes (Hell)
Forte: Physical
Weakness: Cold
Act II
Hack'n'Slash
Location: Stony Tomb Level 2
Boss scroll: No
Forte: -
Weakness: Magic
Note: A superunique boss, doesn't drop quest item
Firewind
Location: Palace Sewers Level 3
Boss scroll: Yes (NM, Hell)
Forte: Fire
Weakness: Lightning
Deathclaw
Location: Palace Sewers Level 3
Boss scroll: Yes (NM, Hell)
Forte: Physical
Weakness: Magic
Hideous
Location: Palace Sewers Level 3
Boss scroll: Yes (NM, Hell)
Forte: Lightning
Weakness: Physical
Act III
Swampface
Location: Swampy Pit Level 3
Boss scroll: Yes (NM, Hell)
Forte: Physical
Weakness: Poison
Darkblood
Location: Disused Fane
Boss scroll: Yes (NM, Hell)
Forte: Magic
Weakness: Cold
Treefoot
Location: Forgotten Reliquary
Boss scroll: Yes (NM, Hell)
Forte: Fire
Weakness: Lightning
Graytongue
Location: Forgotten Temple
Boss scroll: Yes (Hell)
Forte: Lightning
Weakness: Fire
Spellfire
Location: Ruined Fane
Boss scroll: Yes (Hell)
Forte: Cold
Weakness: Magic
Arrowtwist
Location: Disused Reliquary
Boss scroll: Yes (Hell)
Forte: Poison
Weakness: Physical
Act IV
Note: This act doesn't have any superbosses, but has some new superunique monsters.
Act V
Sin Walkers
Location: Abaddon / Pit of Acheron / Infernal Pit
Boss scroll: Yes (Hell)
Forte: Cold / Lightning / Fire
Weakness: Fire / Cold / Lightning
Hope this overview is helpful and you've learned something new. Have you got any question? Leave a comment below!
Wish you happy playing and successful hunting!