Radiance

To unlock this boss you must complete 4 major things.

1. You have to have unlocked the Hollow Knight bossfight by defeating the three dreamers
2. You have to have obtained the first white fragment by defeating the traitor lord bossfight in queens gardens and talking to the wight lady
3. You have to have awakened the dreamnail by finding 1800 essence and used it to enter the white palace, in the wight palace you must complete the hard parkour that is fond inside and get to the white kings corpse, hit the corpse to obtain the second white fragment completing the kings soul charm.
4. Once you've obtained the kings soul you must go down into the abyss where you can use Desolate Dive to destroy the floor where it is now shaking, go down the pit and make your way through the maze of tunnels until you find the black egg where you will see your reflection, dreamnail your reflection and complete the memory sequence and unlock the void heart.

Now you have unlocked the radiance bossfight.

Once you have unlocked the Radiance you need to go to the Black Egg in Forgotten Crossroads. When you enter the temple of the black egg you will see Hornet.
If Hornet doesn't appear then you missed something while unlocking the Radiance, if she does appear then proceed into the Black Egg and fight the Hollow Knight. Instead of beating the Hollow Knight fight it until Hornet appears and stabs it in the head. once that happens Dreamnail the boss and enter the Radiances realm.

A good charm build to use is a combo of Mark of pride. Quick Slash, Unbreakable Heart, and Longnail.

Once you are in the Radiances realm climb up the platforms and challenge the Radiance.


Phase one has a total of 6 attacks
1-It will move a laser across the screen that you must shade dash through
2-It will shoot a circle of blades out of its face, during this attack it is a good Idea to figure out where they will go and then heal 1 mask
3-It will shoot lasers out of its face the lasers are broadcasted before they appear
4-It brings blades of light down from the top of the screen, you have to go beneath the gaps between the blades
5-It brings the blades across the screen sideways and you have to jump up into the gaps between them
6-This is the most annoying attack. It spawns in orbs of light that will follow you around until they collide with something.

This stage is pretty much the same as stage one except now it will spawn spikes in the floor making it so that you cannot use half of the ground.
You will know this stage is ending when it cuts off the edges of the floor a continuously spans in blades from the ceiling.

This stage begins when the boss falls to the ground. During the time it is down you can safely heal 5 masks maybe 6

After that the boss will disappear and the void on the ground starts rising.

Climb up the platforms that spawn and continue fighting the boss on the arena which is now made up of floating platforms.

The boss will do the same attacks but now teleports all over the arena making it where you have to parkour over to the boss each time.

Upon completing the third stage the boss will teleport up and the void will start rising again.

When this happens new platforms will appear, climb up the new platforms avoiding the bosses lasers until you reach the top.

Once you reach the top hit the boss, this will start the ending cutscene and finish the bossfight.

Congratulations you just beat the Radiance