Marius was an unfortunate soul who was caught up in the return of the Prime Evils. He would pay a heavy price for his involvement.
In Terror's Wake
"Why did I follow him...? I don't know. Why do things happen as they do in dreams? All I know is that, when he beckoned... I had to follow him. From that moment, we traveled together, East. Always... into the East."
— Marius recounting his experiences(src)
An old vagrant, Marius had sought shelter in the Rogue Monastery when Diablo's hellspawn overwhelmed the citadel. He fled, finding refuge in a small hostel along with other outcasts and fighting nightmares of the attack, doing his best to stay awake, smoking opium while he did so. But Diablo, in the guise of the Dark Wanderer, stopped at the same hostel, and the place was quickly destroyed by the demons that his presence called up. Being the only survivor, Marius was compelled to follow the Wanderer.
The pair traveled east, over the mountains, and into the deserts of Aranoch. As they walked, the Wanderer spoke of his past, how he had once been a great warrior, how a dark and secret burden now weighed heavily upon them. It was a long and arduous journey, but finally, they came within sight of their destination—Lut Gholein. Making camp, Marius found himself able to sleep again, for the first time in weeks. Yet he dreamed. Dreamed of memories that were not his own. In them, he saw an image of Tal Rasha, and the archangel Tyrael. In the dream, he witnessed the Horadrim binding the mage in order to keep Baal imprisoned within him. Awaking with a start, Marius found the Wanderer looking over him. He cryptically told Marius that he had seen his "brother." The one he sought.
At dawn, the two set out, searching for the Tomb of Tal Rasha. Finding it, and against his better judgment, Marius entered the tomb with his companion. As they made their way through the gloom, he sensed the changes in the Wanderer as Diablo's spirit gained control. Reaching Tal Rasha's Chamber, Diablo rushed forward to release Baal but was intercepted by a newly arrived Tyrael. As the demon and angel fought, Tal Rasha's crazed spirit pleaded with Marius to release him. Marius pulled Baal's soulstone that contained the demon's essence from Tal Rasha's ribcage, releasing Baal from his prison. Before being overwhelmed by his foes, Tyrael charged Marius with going to the Burning Hells and destroying Baal's soulstone at the Hellforge; he ran out of the tomb as Baal joined the battle against Tyrael.
Pathway to Madness
"Oh, forgive me, Tyrael, please. It... wasn't my fault.
Not your fault? Tell me Marius, how was it 'not your fault'?"
— Marius and "Tyrael," in light of the former's failure(src)
Following Tyrael's instructions, Marius traveled to Kurast and gained entry to the Temple of Light There, in its depths, he found the three Prime Evils gathered, summoning the portal he had been instructed to go through. He watched as the Wanderer lost what was left of his humanity, completing his transformation into Diablo, who passed through the gate into Hell. Horrified by what he had seen, he could not bring himself to step through the gate.
Having failed to enter Hell, Marius fled to Westmarch. There, driven to the brink of madness, he was arrested and confined to a sanitarium. His mind shattered, he carved the accounts of his experience into the floor of his cell with his own fingernails. Baal's soulstone also ravaged his body, giving him an aged appearance. A small measure of comfort existed in that word reached his ears at some point of Diablo's defeat, and that his soulstone (along with Mephisto's) were destroyed in the Hellforge.
One day, Marius received a cloaked visitor—Tyrael. Marius, consumed with guilt, related his account to the angel, from the moment he first encountered the Dark Wanderer to his current position. Tyrael assured him that all would be forgiven if he handed over the soulstone, an offer that Marius gladly accepted. What was less heartening was the revelation that his visitor in his cell was not Tyrael, but in actual fact, Baal. Marius broke into tears before Baal "rewarded" Marius for his service, killing him and setting the sanitarium ablaze.
"You abandoned me in that foul asylum, Tyrael! Why did you forsake me when you knew Baal still walked among us?"
— A vision of Marius taunting Tyrael(src)
Marius's failure to ensure the destruction of Baal's soulstone would have dire ramifications for Sanctuary. Ultimately, Baal was defeated, but not before the corruption and subsequent destruction of the Worldstone. Deckard Cain visited the burnt out sanitarium where he had been killed, and was able to read the story Marius had inscribed on the walls of his cell, despite the damage that Baal's fire had inflicted. Marius's charred corpse still remained in the cell.
Twenty years after his death, the Great Conflict came to a head, with a revived Diablo invading the High Heavens. A vision of Marius was used by the Prime Evil to demoralize Tyrael. However, when the angel refused to kneel, the vision was replaced by one of Baal's lieutenants, whom Tyrael and his allies summarily defeated.
Marius makes no appearance in the Diablo II game engine, but does serve as the game's narrator.
A vision of Marius appears in Act IV of Diablo III as part of Diablo's attempt to demoralize Tyrael. When Tyrael successfully fights back the guilt, the vision is replaced by one of Baal's lieutenants, who attempts to stop Tyrael and the nephalem using more conventional means.
Personality and Traits
Marius was heavily scarred by his ordeal from surviving the attack of Diablo's hellspawn at Rogue Monastery, constantly plagued by nightmares and visions that forced him to stay awake. Marius was easily manipulated by both Diablo and Baal on separate occasions.
- Marius was voiced by Frank Gorshin.