Legendary Herobrine
Summon Herobrine through a ritual you have to defend, then beat him in a three-phase boss fight you win by learning his moves.
The Stalker
His first phase. Sword in one hand, pickaxe in the other.
Rite of Summoning
Four soul braziers, a circle of runes and a storm that keeps putting them out.
Keep the flames lit
The rite only moves forward while the braziers burn.
The Tear
In the last stage a rift opens over the altar.
He came
Right after the rite ends.
Dash Slash
The line of light shows where he's going. Step off it.
Sword Wave
Jump it or sidestep it. Blocks stop it.
Whirlwind
He's slow while he spins, and dizzy for a moment after.
Ring of fire
It rolls outward from him. Jump it.
Gaze Beam
It turns slower than you can run around him, and blocks stop it.
Mirror images
Only the real one's eyes glow.
Meteor dive
The circle stops following you just before he lands. That's when you move.
Unbound
His last phase. Everything gets faster.
A sighting
Before you ever summon him, he's out there watching.
The relics
Enhanced Sword, Herobrine's Pickaxe and the Builder's Crown.