Skeletal Avenger
21 Achievements
GOG
Sewage Treatement
Kill Sewer boss.
8.3%
How to unlock the Sewage Treatement achievement in Skeletal Avenger - Definitive Guide
You'll need to collect 50 red stones from other quests in order to open up the boss level quest in the sewers ("The Gutter" - 2nd area).
Having a pretty upgraded skull and weapons in the upgrades section is really helpful and some good items as well. I equipped the War trinket to give me +2 to all stats. Your choice of clothing items and perks may vary but here is what I used for most of my playthrough:
Melee Weapon: Hammer (highest damage output and stuns enemies as you hit them)
Skull Type: Ram Horns Helmet (highest damage output, great for bosses and individual enemies)
Perks: Usually Hothead and other perks that raise skull damage and add fire damage or necrotic pools.
When fighting the boss, I would fire the skull at the boss, then dash in to pick it back up while getting off a hit with my hammer and dashing back out. Rinse and repeat until the area boss is dead and you're golden.
Having a pretty upgraded skull and weapons in the upgrades section is really helpful and some good items as well. I equipped the War trinket to give me +2 to all stats. Your choice of clothing items and perks may vary but here is what I used for most of my playthrough:
Melee Weapon: Hammer (highest damage output and stuns enemies as you hit them)
Skull Type: Ram Horns Helmet (highest damage output, great for bosses and individual enemies)
Perks: Usually Hothead and other perks that raise skull damage and add fire damage or necrotic pools.
When fighting the boss, I would fire the skull at the boss, then dash in to pick it back up while getting off a hit with my hammer and dashing back out. Rinse and repeat until the area boss is dead and you're golden.