Moon Phases are world states in Bloodborne. Depending on specific events and conditions during the game, the sky will change colors and the inhabitants of the world will react differently. Some quests and secrets have special conditions that must be under a specific phase.
|Defeating Rom, the Vacuous Spider and approaching the blood soaked lady in white will bring in the Blood Moon phase
NPCs can no longer be saved, Arianna and Adella no longer provide blood.
All Lesser Amygdalae are permanently visible, no longer requiring 40 Insight to see.
You won't be able to awaken in the Hypogean Gaol lamp.
Old Yharnam, Forbidden Woods and Forsaken Castle Cainhurst still have a white moon during this phase.
Defeating Gehrman, the First Hunter and encountering the Moon Presence will bring the Blood Moon to Hunter's Dream.