Most fans of Diablo that played through Diablo 4's main campaign story have nothing but praise for the cinematics. The initial reveal of Diablo 4 with the "By Three They Come" cinematic – which depicts Lilith's arrival on Sanctuary – immediately set a tone for what players could expect from this fourth installment. It wasn't just a cinematic, though.
In fact, the area that Symon, Elias, and the two mercenaries explore can be visited as part of a side quest chain. It begins in Hawezar, south of the Fractured Peaks, and takes players through four parts that go into more detail about the seemingly ragtag group of graverobbers Elias deceived, and ends in the very room where Lilith was summoned to Sanctuary.
Part One: To Walk A Dark Path
Working with a Demon, no matter what deal was struck, is a dark path to walk for any denizen of Sanctuary – Symon, a Curate of Akarat, found that out without knowing it. In the Diablo 4 intro cinematic titled By Three They Come, Curate Symon is the priest who was ushered unknowingly into Lilith's summoning chamber by Elias, who promised him knowledge. Though Father Dymus warned him against Elias, who was portraying himself as a swordsman in Zarbinzet, Symon was enamored with his words.
This first part of the questline sees players follow Symon's footsteps as he and the swordsman travel east – always, to the east. The By Three They Come quest begins upon talking to Father Dymus at the northern end of Zarbinzet. Open your world map and mark the location of the first objective, Symon's writings. Here, he reveals that he and the swordsman traveled further east to stop by the statue of Tibault.
Upon arriving, the player is accosted by two people haunted by Elias. After beating some sense into them, players can interrogate them to find that Symon and Elias passed through. They headed to a hidden camp (not the one from Diablo 3), one marked by tusks in the marshes... to the east.
Part Two: At Any Cost
The frightened pilgrims guide players to the marshes of Hawezar, to a cabin noticeably devoid of Elias or Symon. As players know, Symon is long gone by the time Lilith enters Sanctuary, but the player's character is tasked with finding traces of their presence anyway. After interacting with each of the objects in the camp, a seemingly dead Acolyte of Rathma will speak.
It comes to life, and tells the player to take its head for an old spell that should aid their search. The risen corpse of the acolyte fights back, but will drop its head on defeat.
The head of the acolyte instructs players to light three candles, which shows a vision of Elias encountering the Acolyte of Rathma here in his one-eyed swordsman disguise. The acolyte was hunting Elias, and after Symon discovered the body, Elias says they must hurry to Backwater. Then, the vision ends.
Part Three: Turbulent Waters
The third part of the By Three They Come questline begins after players conclude their time in the secret camp. On the other side of Hawezar lies the port town of Backwater, where players must go next to find out what became of Symon. Look for a man named Nivro, who sits to the south of the center of town at a gem stand. Players learn of Sev, one of Symon's party members, and the only one who came back alive.
Be sure to have at least a little bit of gold on you to buy his Mead for Sev, as she won't talk until she gets some. Found overlooking the sea edge south of Backwater, she describes the experience and why she fled. She also names the other two characters featured in the intro cutscene to Diablo 4: Fionn, a Scosglen rogue (and the first of the three recruits to die), and Gelwa, a barbarian from the Dry Steppes who witnessed Elias' transformation from swordsman to Servant of Hell.
After players inform Sev that Elias is dead, she reveals that the group journeyed to Esret in search of "treasure" and "knowledge". Conveniently, this location is just southeast of Zarbinzet in the Fethis Wetlands.
Part Four: By Three They Come
Fast travel back to Zarbinzet and head southeast out of the city – be sure to mark the quest location on the world map to get in-game guidance on the mini-map, too. After arriving at the Accursed Ruins of Esret, Sev will leave the player to go down a Hole of Dark Portent dug beneath an old chapel.
This is the same hole that the opening cutscene starts with, whens the camera zooms down its depths and to Symon and the gang. In perhaps what might be a callback to the original Diablo, which took place entirely beneath Tristram, players must go down this hole to discover the place where the game's main demon was summoned.
The Halls of Dark Portent aren't too remarkable, offering a few hellish enemeis to take out but nothing too overwhelming. Several other locations from the cinematic can be found here. For instance, the entrance to the Ancient Gate still has fresh stains from Symon and others willingly giving their blood, but players must instead use their raw power to break down the stone door.
After beating the ghouls and getting inside, players confront a Blood Echo, a boss which appears to be a remnant of Lilith's blasphemous summoning. After only getting a moment or two to admire the blood petals that adorn the Ancient Gate's elaborate (and gorgeously lit) room, the boss spawns.
The Blood Echo has an attack that makes targets vulnerable with a flurry of shots as well as a deadly grab, so be sure to keep defensives up and move in a circle to stay on its rear, and stay safe. Though not a particularly tough boss battle, it can be surprisingly agile.
After killing the Blood Echo, players will discover the body of Symon slumped over the northeasternmost pillar. On his body is Symon's Tattered Journal, which explains his apprehension towards the final steps of the journey in his own words. Bring this back to Father Dymus in Zarbinzet to complete the By Three They Come quest chain (and get the achievement, too).
Diablo 4 is available for PC, PlayStation 4 and 5, and Xbox One and Series X|S