Dream Nail

Function
Hold down DREAM NAIL to charge and swing the Dream Nail. This can perform several functions:
 * Extract Essence from Ghosts
 * Activate Whispering Roots
 * Collect SOUL from living enemies (33 SOUL)
 * Challenge Warrior Dreams
 * Challenge Dream Bosses
 * Enter the minds of Dreamers
 * Access the Shrine of Believers
 * Access the White Palace (Awoken Dream Nail)
 * Instantly kill both the Shade and Siblings
 * Obtain Void Heart
 * Challenge The Radiance
 * Summon The Grimm Troupe
 * Access Godhome
 * Switch boss forms in Hall of Gods
 * Read the minds of NPCs, enemies (excluding Warrior Dreams), some statues and corpses
 * Use to set or travel to a Dream Gate (Requires 900 Essence)

The Dream Wielder charm, granted by the Seer after collecting 500 Essence, greatly reduces the charge time of the Dream Nail and doubles the SOUL gained from hitting living enemies (from 33 to 66).

Awoken Dream Nail After collecting 1800 Essence, the Dream Nail can be awoken. This allows access to dreams and memories that were previously hidden. The Awoken Dream Nail can be used on the corpse of the Kingsmould in the Palace Grounds. This will grant entry to the White Palace.

Furthermore, the Awoken Dream Nail can be used to view the Dream Nail dialogue of the Shade Cloak creature in The Abyss. This creature has different Dream Nail dialogue depending on whether Void Heart has been obtained.

How to Acquire
The Dream Nail is acquired in the Resting Grounds by inspecting the Dreamer Statues. Doing so will send the Knight into a dream where they will receive the Dream Nail from a Moth.

Essence
Essence is the energy gained from multiple sources after obtaining the Dream Nail. After obtaining certain amounts of Essence, the Knight can return to the Seer for rewards. A total of 2400 is needed for all in-game rewards and Achievements, though up to 3208 essence is available from exploration and bosses. Warping using the Dreamgate uses 1 Essence each time.

Essence Sources

 * Using Dream Nail on a Ghost (26 total)
 * Collecting Essence spawned by a Whispering Root (482 total)
 * Defeating a Warrior Dream (1100 total)
 * Defeating a Dream Boss (1600 total)
 * Regular enemies have a chance to drop Essence:
 * Normal chance: 0.5%
 * Dream Wielder equipped: 1%
 * If Essence was spent on warping to a Dreamgate: 2%
 * If Essence was spent on warping to a Dreamgate and Dream Wielder is equipped: 4%

Essence rewards from the Seer

 * 100 Essence - Hallownest Seal
 * 200 Essence - Spirits' Glade opens
 * 300 Essence - Pale Ore
 * 500 Essence - Dream Wielder Charm
 * 600 Essence - Attunement Achievement
 * 700 Essence - Vessel Fragment
 * 900 Essence - Dream Gate
 * 1200 Essence - Arcane Egg
 * 1500 Essence - Mask Shard
 * 1800 Essence - Awaken the Dream Nail and unlocks Awakening Achievement
 * 2400 Essence - Ascension Achievement

Trivia

 * The Dream Nail can be used to push back most enemies.
 * The max amount of Essence that can be stored is 2,147,483,647 (over 2 billion).
 * Even though the Fluke Larvas near Flukemarm and in Junk Pit are not considered as actual enemies in-game, they will still have a chance to give 1 Essence after being destroyed.
 * Certain NPCs can sense their mind being read, namely the White Lady, Snail Shaman, Bardoon, Seer and Midwife.

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