The Kingsoul upgrade that unifies the void under the Knight's will. 0 notches, permanent slot, gates the true ending and the Embrace the Void path.
Void Heart is the only charm in Hollow Knight that cannot be unequipped. Per the wiki, the moment the Knight returns to the Abyss with both Kingsoul halves collected and the Kingsoul charm equipped, a hidden door at the bottom of the chasm opens into the Birthplace; stepping through triggers a cinematic that permanently converts Kingsoul to Void Heart in the inventory.
According to the wiki, the conversion drops the notch cost from 5 (Kingsoul) to 0 (Void Heart) and locks the charm slot. The charm's effect changes from a slow SOUL-regen aura into something more narrative: it unifies the void siblings under the Knight's command, unlocks the Dream No More true ending against the Hollow Knight, and gates the Embrace the Void ending after the Absolute Radiance fight in Pantheon of Hallownest.
The wiki specifies the gameplay impact is enormous despite the 0-notch tag. Void Heart turns the Shade siblings hostile-on-sight into allies that follow the Knight through certain encounters, makes The Radiance fight available via the Awoken Dream Nail, and is the lore-confirmed reason the Knight wins the void tendril struggle in the final cinematic.
This guide covers Void Heart's acquisition sequence, the Kingsoul half collection, the Abyss descent, the gameplay effect, the two endings it unlocks, and the lore reading the wiki backs up.
The Kingsoul upgrade earned at the Birthplace in the Abyss.
0 notches (permanent slot), cannot be unequipped after the cinematic.
Both Kingsoul halves from White Lady and Pale King's corpse.
Dream No More true ending + Embrace the Void capstone.Void Heart is a permanent 0-notch charm that rewrites the Knight's relationship with the void. Per the wiki, the description reads "An emptiness that was hidden within, now unconstrained. Unifies the void under the bearer's will." In gameplay, this means the Shade siblings in the Abyss stop attacking, the Awoken Dream Nail can be used on the Hollow Knight corpse, and the final cinematic changes depending on whether Void Heart is in the inventory.
According to the wiki, the 0-notch cost is the single most efficient charm slot in the game. Every other charm pays 1 to 5 notches for its effect; Void Heart pays nothing and never comes off. The trade-off is the locked slot itself: 1 of the 11 charm slots in the inventory is now occupied by Void Heart for the rest of the save, but since the cost is zero, the budget is untouched.
The wiki specifies the charm fires the Dream No More ending sequence. With Void Heart equipped (and it cannot be unequipped, so this is automatic), the Knight uses the Awoken Dream Nail on the Hollow Knight during the final encounter; Hornet arrives mid-fight and seals the Knight's sibling into the dream so the Radiance can be confronted directly.
| Stat | Value |
|---|---|
| Notch cost | 0 |
| Predecessor | Kingsoul (5 notches) |
| Location | Birthplace, bottom of The Abyss |
| Requirement | Kingsoul equipped (both halves collected) |
| Effect | Unifies the void under the Knight's will |
| Equip state | Permanent (cannot be unequipped) |
| Endings unlocked | Dream No More + Embrace the Void |
| Charm number | 36 (the secret slot in the Charm Collection) |
Per the wiki, Void Heart occupies the final secret slot in the Charm Collection menu. The slot displays as locked until the conversion happens; afterwards the icon shows the white-on-dark void sigil and the description text reveals "Unifies the void under the bearer's will."
The path is a 5-step chain. Per the wiki, the Knight needs both Kingsoul halves first, then equipping the assembled Kingsoul and descending into the Abyss opens the Birthplace door automatically.
Per the wiki, the Birthplace door checks the Kingsoul equip state, not just inventory possession. Players who walk to the Abyss bottom with Kingsoul in inventory but unequipped see no door. Re-equip at the nearest bench (the Hidden Station or City of Tears) and return to the Abyss bottom; the door opens automatically.
Void Heart gates two endings and changes a third. Per the wiki, the three Void-Heart-aware endings are Dream No More (true ending), Embrace the Void (post-Godmaster capstone), and a passive change to the standard "The Hollow Knight" ending.
Dream No MoreAccording to the wiki, Dream No More fires when the Knight uses the Awoken Dream Nail on the Hollow Knight during the Black Egg fight. Void Heart equipped is the gate; without it, the Awoken Dream Nail bounces off. With it, the Knight enters the Hollow Knight's dream and faces The Radiance directly. Killing the Radiance triggers the true ending cinematic where the Knight's siblings consume the Radiance and the void replaces the Hollow Knight's seal.
Embrace the VoidPer the wiki, Embrace the Void is the Godmaster DLC capstone. The Knight clears Pantheon of Hallownest (the 42-fight chain), defeats Absolute Radiance at the top, and the cinematic shifts to show the void consuming both the Radiance and the Godseeker who hosted the Pantheon. This ending only fires with Void Heart equipped at the time of the Absolute Radiance kill.
The Hollow Knight (default)The wiki specifies that the default "The Hollow Knight" ending fires when the Knight kills the Hollow Knight without Void Heart equipped. The cinematic shows the Knight replacing the Hollow Knight inside the Black Egg as the new seal; the Radiance remains sealed but the Knight is now the prisoner. Void Heart is required to escape this loop.
The void siblings reading is the canonical lore hook. Per the wiki, the Vessels in the Abyss are every prior child of the Pale King and White Lady; they were created to seal the Radiance but most failed and died inside the Abyss. The Knight is the last functional Vessel; Void Heart is the moment when the Knight gains command over its shade siblings.
According to the wiki, the Birthplace cinematic reveals the Knight emerging from the void mass at the bottom of the Abyss as a newborn Vessel. The shade siblings reach toward the Knight from the walls; the cinematic ends with the Knight absorbing the unified void into its own shade, which is what the charm description means by "unifies the void under the bearer's will."
The wiki effects block notes the symmetry with the Pale King's plan. The Pale King wanted a perfect, empty Vessel to contain the Radiance; the Knight, by gaining Void Heart, becomes the opposite: a Vessel filled with the void it was supposed to be empty of. The true ending dispatches the Radiance using the opposite of what the Pale King designed.
Since Void Heart costs 0 notches, the entire 11-notch budget is free for the rest of the loadout. Per the wiki, the standard endgame build slots Quick Slash, Mark of Pride, Unbreakable Strength, and Quick Focus alongside Void Heart for a combat-leaning loadout.
Void Heart (0 notches; permanent) Quick Slash (3 notches; faster nail strikes)
Mark of Pride (3 notches; +25% reach)
Unbreakable Strength (3 notches; +50% nail damage)
Quick Focus (3 notches; faster heals)According to the wiki, this 12-notch combat loadout overcharms by 1 notch but Void Heart's zero cost keeps the penalty light. The Radiance fight requires this exact loadout in most Embrace the Void runs because the spike damage from Unbreakable Strength shortens Phase 5 enough to survive the Spike Floor sequence.
Void Heart ties to the Kingsoul questline, the Abyss exploration, the true ending sequence, and the Godmaster DLC capstone. These spokes pick up the threads.
Game data and screenshots adapted from hollowknight.fandom.com, used under CC BY-SA 3.0. Original content remains the property of the wiki contributors and Team Cherry.