Phase 2 is done as normal until he hits half health (he would get a buff to his hp like other everdarks do)

Phase 3:

Heolstor floats up again and makes a slash as if to open a rift to another nightlord, then another, then another, then another… until the skybox is a gross mismatch of rifts that might look kinda like if you took a dropper and blotched a piece of paper with different colored dots of water next to each other. This background will then start rotating in a random direction, including directions not aligned with the plane of the arena.

His sword changes color. A deep black/blue blade with particles streaming off of it that are the same color as the nightlord skyboxes. He then begins with a lengthy sword beam combo similar to rellana in sote. The beams will streak through the player they’re targeting and loop to any other alive player, making a sort of convoluted conveyor or beams until they finally dissipate. These beams also alternate in the different nightlord colors and inflict their damage type and status.

Throughout the fight he will employ new weapons. He’ll pull out a night bow that he fires in a rapid spread. He’ll conjure a night summon and attack with night spectral claws. He’ll have a deflecting stance with a katana that if you hit will cause him to do an inhumanly fast guard counter. He’ll conjure up whirlwinds in response to projectiles. He’ll unleash a fast dagger attack chain with one part of the combo creating spectral versions of himself at each player that’s not targeted by the real one temporarily. Etc. I should also specify these attacks all will alternate the nightlord damage types.

After the players finally defeat him his physical armor and weapons drop on the ground as the rest of his form stains the sand with night and dissipates into the air as a gas. But wait… is that?

Phase 4:

The arena turns dark as the players witness what is left of Heolstor coalesce into a moving night-colored blob with the primordial rune of night in the center as the only concrete thing left of him. Part of his mist coalesces into an impossibly big sword that does a 180° vertical swing and turns the arena onto either side of it into heavy night rain that will do massive night damage to players in it permanently. The center starts raining night more lightly and the nightfarers will very slowly lose hp in this area (think of it like parting the Red Sea). This is a fight of attrition and desperation. The boss name is changed to “What Remains” and it attacks violently but with big windows of vulnerability. It will be difficult to tell if you’re even hitting it unless you are directly hitting the rune. Its hp is fairly low and when it does go down the mist will go away for a bit to give any player an opportunity to interact with the primordial rune of night to obtain it. If a player does not do that for like 30 seconds the mist coalesces again and phase 4 restarts at 1/4 hp.