Radiance

Behaviour
The Radiance is the true final boss of Hollow Knight. To access her, the player must have acquired Void Heart and have used the Dream Nail on the Hollow Knight when Hornet holds them down to be able to challenge her. {{CollapseTable|More...| In the first phase of the fight, she levitates slightly above the floor. Only her body is vulnerable to attack, which requires jumping or ranged attacks. She will often teleport around, making it even harder to get a good string of hits in while avoiding her own ruthless attacks.

The Radiance does not deal contact damage, however, all of her attacks (except hazards like spikes and the Void) deal two masks damage upon hit, making her by far the hardest-hitting boss in the game.


 * Beam Burst: The Radiance will fire multiple beams of light from her face, 3 times. This attack occurs in Phases 1, 2, and 4. Each burst consists of 8 beams spread evenly around the Radiance at 45 degree angles. Each burst of beams is rotated randomly from the previous burst. The beams are dangerous for about half of a second and only when the beams are at their widest.
 * Sword Burst: The Radiance will shoot 12 swords from her face. This attack occurs in Phases 1, 2, and 4. These swords point outward in a burst-like formation. The swords form one at a time, circling the Radiance's face either in a clockwise or counter-clockwise order but the circle starts with a random sword. Once all swords are formed, the Radiance tilts her head forward, launching all swords simultaneously. Each sword travels in the direction it is pointing but curving gently the longer they travel. The angle each sword points at can be different for each attack.
 * Sword Rain: The Radiance summons swords to rain down on us from the top of the arena. This attack occurs in Phases 1 - 3. These swords will move as a group. Each group of swords is comprised of 12 swords arranged randomly across 18 columns. The columns upon which the swords travel shift to the left or right slightly with each group. There will always be large safe spaces between some swords and even the space between 2 adjacent swords is wide enough to stand in. In Phases 1 and 2, this attack will involve 4 groups of swords. Group 2 starts 1.5 seconds after group 1. Groups 3 and 4 start 1 second after groups 2 and 3, respectively. In Phase 3, there is an infinite amount of swords and each group starts within 1 second of the previous group.
 * Sword Wall: The Radiance summons walls of swords to shoot across the arena. This attack occurs in Phases 1, 2, and 4. These swords will move as a group across the arena left to right or right to left. Each wall of swords is comprised of 6 swords arranged randomly along 9 rows, ensuring that there will always be some gaps that The Knight can fit in. In Phases 1 and 2, this attack involves 4 walls of swords. Wall 2 starts 2 seconds after wall 1. Walls 3 and 4 start about 1.5 seconds after walls 2 and 3, respectively. In Phase 4, 2 walls are summoned. Wall 2 starts 2 seconds after wall 1. Each wall of swords takes about 3 seconds to cross the arena. During this attack, all walls travel in the same direction.
 * Wall of Light: The Radiance summons a wall of light that crosses the arena. This attack occurs in Phases 1, 2, and 4. This wall of light crosses the arena from left to right or right to left. The wall takes about 3.5 seconds to cross the floor. The dangerous part of the wall is the large, wide beam. The leading and trailing lines of light are harmless. The wall moves about as fast as The Knight does when dashing. There is a variation to this attack which involves the wall of light disappearing at the middle of the arena. A second wall of light may spawn just as soon as that first wall reaches the middle of the arena. The only way to avoid this attack is by using Shade Cloak.
 * Orb: The Radiance will summon 3 orbs of light that home in on The Knight. This attack occurs in Phases 1, 2, and 4. Each orb appearing about 1.5 seconds after the previous. Orbs will track The Knight until they strike The Knight, strike a surface, or disappear. An orb will disappear after about 3 seconds if it doesn't hit anything. Orbs can pass through surfaces in their first half second of life. Orbs can spawn from anywhere.
 * Spike Floor: The Radiance will cover part of the floor with spikes. This attack occurs in Phases 2 and 3. In Phase 2, the spikes will be in one group, cover 50% of the floor, and persist for 5 seconds. In Phase 3, the spikes persist forever and there can be 2 groups of spikes on each side of the floor covering a total of 50% the floor or just one group on one side covering 25% of the floor. Unlike every other Radiance attack, the spikes do 1 mask of damage.
 * Big Beam: The Radiance fires a single, large beam of light. This attack only occurs in Phase 5. The beam's accuracy improves the further into Phase 5 the player gets. The beam is dangerous for about .25 seconds and only when the beam is at its widest. A beam is fired every 1.5 seconds.

In Phase 1, The Radiance will simply use these attacks while hovering above the floor and teleporting. The hardest attacks to avoid are typically the horizontal walls of swords and the homing projectiles. It's very important not to try to panic-heal, despite the massive damage of her attacks, as any mistake in this fight is extremely costly. Wait for a good occasion to heal, such as during the third salvo of the eye beams.

In Phase 2, The Radiance continues using the same attacks, but will now create spikes across alternating halves of the platform. The restrained space makes it much harder to maneuver and to stall out the cooldown of the Shadow Dash. She will switch the location of the spikes every 5 seconds, outlining their new location with a golden glow for about 2 seconds as a warning before they actually emerge. These spikes only deal one mask of damage. The strategy remains mostly the same, but more precise dodging will often be necessary.

In Phase 3, The Radiance will float in the center of the platform, place spikes at the edges and endlessly rain down swords from above. Since this is one of the easier attacks to avoid, this acts mostly as a breather phase.

In Phase 4, The Radiance resumes using all of her normal attacks, but she is now fought on a field of small platforms over the Void. This makes all of her attacks much harder to dodge without accidentally falling down into the Void and taking damage; put the double jump to good use. On the bright side, while she will still teleport around, it is still possible to hit her without jumping if she teleports close to a platform.

The last phase, Phase 5, involves ascending by jumping up platforms as The Radiance flees again. Her only attack in this phase is the Big Beam. Upon reaching the Radiance, hit her one more time with the Nail to end the fight and trigger the final sequence.

In the final sequence, The Radiance is bound by Void Tendrils and the shade of the Hollow Knight appears, tearing open a weak point on her face. The Knight bursts out of their body and becomes their Shade. Attacking causes the Shade to repeatedly whip The Radiance's weak point with long tendrils until it's defeated and dragged into the Void below.{{Spacer}}As with most boss fights, Quick Focus is highly recommended. Since occasions to hit the Radiance are not too frequent and her attacks deal a lot of damage, SOUL-generation charms like Soul Catcher and Grubsong are also suggested. Fragile Strength can be a lifesaver by increasing damage output tremendously (to prevent the Charm from breaking, simply pause the game and reload before dying). {{Spacer}}

Tactics
It should be noted that in the first three phases, the swordbeams from Grubberfly's Elegy can be used to hit The Radiance without jumping, which can be especially useful when combined with Quick Slash.

Joni's Blessing and Lifeblood Heart/Core can be useful for those finding it hard to heal.

A spell-focused build can be employed by forgoing any healing Charms for the Lifeblood charms described above along with Shaman Stone, allowing the player to spam Abyss Shriek to get quick and easy damage off, as the Radiance does not get knocked back and will take all four hits of the Spell.}}

Trivia
"The moth tribe were (perhaps) descended from Radiance. However, the King convinced them somehow to seal Radiance away. I guess so he could rule Hallownest with his singular vision, as a monarch/god with no other gods.The moths sealed Radiance away by forgetting about her. Hallownest was born and flourished. However, the memory of Radiance lingered (eg the statue at hallownest's crown) and soon she began to reappear in dreams and starting exerting influence. The King and the bugs of hallownest resisted this memory/power and it started to manifest as the infection. Thus the first attempt to seal Radiance failed, and the King had to try another method - the Vessel." Сияние
 * Beating the Radiance is not required to complete the Hunter's Journal, but she does have an entry.
 * Through HUD manipulation, The Radiance is shown to actually have 3000 health, though the "fight" portion of the battle ends when she reaches 1300 health, effectively requiring the player to only have to deal 1700 damage to win the fight.
 * The Radiance is confirmed to be female from developer commentary on Slack, as well as from developer notes regarding the Seer:
 * The Radiance is one of the two bosses that must be challenged to battle, the other being the Mantis Lords. While the Mantis Lords will have to be challenged every time, the Radiance's intro is abridged after the first time fighting it, causing her to attack directly upon entering her arena.