Fury of the Fallen

Fury of the Fallen is a Charm in Hollow Knight. It increases Nail damage by 75% when at 1 Mask.

Usefulness
Fury of the Fallen only affects Nail damage, so a build using this Charm should be Nail-focused and not Spell-focused. It does not affect the damage of the Sharp Shadow, Dreamshield, and Thorns of Agony Charms.

Since the ability requires the Knight to be in a near-death state, it is most useful in builds where the Knight tends to get damaged a lot or builds designed to intentionally bring the Knight down to 1 Mask, such as speedrunning where the Knight can reliably dodge most attacks.

In a regular game, Fury of the Fallen is only useful if the Knight is able to avoid taking the last hit of damage for long enough to get in Nail hits. Using the Quick Slash and Grubberfly's Elegy Charms to deal more damage faster or from a safer distance is recommended. Otherwise, it is more advised to use a Charm like Quick Focus to bring the Knight back into the fight sooner.

While in the Fury of the Fallen state at one Mask, adding extra Lifeblood Masks onto the end of the health bar does not negate the effect, making this Charm useful for situations such as the Pantheons. Lifeblood Masks from the Joni's Blessing Charm are treated like actual Masks. Due to this, Fury of the Fallen only triggers when the Knight has one Mask remaining.

How to Acquire
Found in King's Pass, the starting cavern, behind a spike-filled cavern. Look for the Geo cluster in the southwest part of the pit room. Dash or Nail-bounce to cross the spikes, and continue east to find the Charm.

Trivia

 * Prior to the Lifeblood update, when Fury of the Fallen was activated, the screen was bordered with wispy red lines and the Knight was circled in a red icon. Subsequently, the red circle was removed and the effect around the Knight was changed to be a red smoke.


 * It is useless if all possible hazards and attacks deal two Masks of damage (such as when Overcharmed) if the Knight has an even number of Masks and has Joni's Blessing or Deep Focus equipped, as this makes it impossible to have an odd number of Masks.
 * It is also useless during Radiant boss fights, as it is not possible to reach one Mask of health.
 * The Knight usually has a hurt idle animation that plays while at 1 Mask; however, it does not play while having this Charm equipped.
 * If the Knight has the Fury of the Fallen, Hiveblood, Joni's Blessing, and Glowing Womb Charms equipped, the effects of Fury of the Fallen all apply normally while at 1 Mask; however, if Hiveblood brings the Knight up to 2 Masks, the Nail and Nail Art damage continue to benefit from Fury of the Fallen while newly-spawned Hatchlings do not.