Here is the full list of all 34 Mary Skelter: Nightmares achievements.
Obtained all Trophies!
Blood Devolution reached Level 80.
Activated a Blood Soul Skill 100 times.
Protected the heroine 100 times.
Complete 80% of the Jail Creature Manual.
Cleared 50% of the work orders.
Cleared the Underground Jail area.
Cleared the Jail Tower.
Unlocked the Good Ending.
Unlocked the Bad Ending.
Cleared the Station Grounds area.
Defeated all Nightmares outside the Jail.
Raised all heroines' affection to max level.
Unlocked all of the heroines' jobs.
Hameln joined your party.
Gained the Blood ability Mary Reverser.
Cleared the Waterside area.
Cleared the Dorm area.
Cleared the Downtown area.
Collected 100,000 Gold.
Cleared the Temple area.
Entered Blood Skelter mode for the first time.
Raised one heroine's affection to max level.
Cleared 10 work orders.
Conducted Purge for the first time.
Cleared the Graveyard area.
Entered a hidden floor.
Filled the Jail Creature Manual with 10 creatures.
Cleared the City Streets area.
Matured a floor.
Satisfied the Jail's Sleep.
Satisfied the Jail's Libido.
Satisfied the Jail's Hunger.
Entered Massacre mode for the first time.