Reference
Achievements
Every achievement, what it asks for, and the rules that can lock one out for a whole save. Boss, Shell and weapon achievements link to the page for that boss, Shell or weapon.
Warning: Slayer Seal
The game asks: “Warning: equipping the Slayer Seal will disable achievements. Do you understand this?”
All 53 achievements are blocked on a save where the Slayer Seal has been equipped. Picking it up does nothing; equipping it does. The HUD then reads “Achievements Blocked”.
Skip Prologue?
“You have the option to skip the Prologue and start a new game just before your arrival at Marrow Keep.”
3 achievements are earned before that point: You're More Than a Weapon, Mid Summer? and No, You Still Can't Win. The Tar Golem one is missable on any save: if you are severed from your Shell the fight ends, and he does not return in New Game Plus.
- L8Lord of War
Unlock all Weapons