Shade Soul

Shade Soul is a Spell in Hollow Knight. Using it conjures a shadow that flies forward and damages enemies.

Function
Press FOCUS/CAST or QUICK CAST without holding UP or DOWN to launch a projectile that passes through enemies and deals damage. The projectile will now penetrate all objects in its path including walls and invulnerable parts of enemies, such as a shield or shell, but will not damage a fully protected enemy.

Modifiers

 * Flukenest turns the Shade Soul into a horde of black baby flukes that bounce around dealing damage.
 * When combined with Defender's Crest, launches a single large fluke that explodes into a damage-dealing cloud of gas.
 * Shaman Stone increases the width of the projectile and the damage dealt by 33%
 * Spell Twister lowers the SOUL cost to cast Shade Soul to 24 SOUL.

How to Acquire
Upgrade to Vengeful Spirit. Requires purchasing the Elegant Key from Sly in Dirtmouth.

The spell is located behind a locked door in Soul Sanctum within the City of Tears. Requires defeating a Soul Warrior that continuously spawns Folly enemies.

Trivia

 * There is an unused version of Shade Soul that consists of a mixture between a black Shade Soul and a white Vengeful Spirit much like how Abyss Shriek combines black souls with white Howling Wraiths.
 * Shade Soul is obtained from a snail shaman linked to some kind of machine. This implies that the researchers of the Soul Sanctum were experimenting on the Shamans' natural ability to use Soul.
 * The tendrils that come out of the Knight's back are similar to those seen on the Knight's Shade at the end of the Radiance fight.

Тень души 暗影之魂 Âme d'ombre