"For the love of God, don't you have anything better to do?!" screamed Steve. Herobrine shrugged, smiling.
"He's done something quite unprecedented. Naturally I have a scientific interest in how it turns out."
"Herobrine, let him go."
"I'm not holding him." Herobrine lifted his hands and looked down at Arix, who started to inch towards the water. Herobrine grabbed him by the nape of the neck. "Kidding. I am holding him." he flipped Arix over and lifted his chin, staring into his eyes. "Hmm. Sure you're a mage? You have to be ruthless, and I don't think you are… then again, people change. Perhaps you'd do better, now. If you hadn't gone and ruined it." he reached for Arix's wrist but Arix hid it behind his back, remembering how Herobrine had brought the mark back the last time. Herobrine frowned and seized his head. It was the same attack he had felt before in the caves, but different. Something in him was missing and this invasion tore at the wound, unable to latch on. He started screaming and didn't stop. "Alright, wow, it did work. Good for you, you broke yourself. Now shut up." Steve ran without slackening his pace to the edge of the stream. Herobrine watched in disbelief as he leapt across the rocks and launched off the furthest point of one, heading straight towards him. Herobrine teleported away at the last second and Steve flew through the air where he'd been and crashed face first into the rock. He turned immediately and stood over Arix, glaring across the stream at Herobrine, who had appeared on the rock he'd jumped from. "Look at you. Able to parkour for once in your life."
"Get out."
Herobrine stared. For several seconds neither moved, and the only sound was Arix whimpering. A trickle of blood ran from Steve's nose into his beard. Then Herobrine shrugged, chuckling. "Keep it if you want it. I don't think it's good for much now, except starting fires." he turned and walked across the blackened field, finally vanishing with a flash near the treeline.

Steve relaxed and took a deep shuddering breath. Then he sank down and pulled Arix to a sitting position. "Are you OK?" Arix opened his mouth to say yes, smelled the blood on his breath, and threw up in Steve's lap. "Oh. Poor guy." he pulled Arix into the water and washed both of them off, trying to get Arix to talk. "I saw the smoke near the end of the day and came back as quickly as I could. Are you alright? Where were you?" Arix silently showed him his wrist. Steve looked at it carefully, then flexed Arix's hand, careful not to hurt him. "Huh. I can't tell if it's that's an improvement or making it worse, yet." he pulled the front of Arix's shirt up to see where the blood on his chest was coming from, and looked for a long time at the cuts across his torso and upper arms. "Was this necessary?" he said, darkly.
"Maybe?" said Arix. Steve picked him up and walked towards the cliff, whistling to the skeleton horse, which followed. Arix let his eyes close. "Steve."
"Yeah?"
"I think someone has it in for me."
"Are you kidding? You should have been dead I don't know how many times now!"
"Yes."
"But you're not dead. You're not dead."
Arix sighed. "Whoopee." Steve squeezed him tighter.

Steve set him down against the base of a charred tree at the top of the cliff. "Wait here, alright?" then he clambered into the mess of blackened boards where half of the treehouse had collapsed. Arix fell into a kind of stupor. He knew Steve was rummaging through the boards, and that he stopped and sank to his knees at one spot, but he didn't consider why. Then he came out, carrying something wrapped in a blanket, set it down and took out a shovel. Arix woke up as he started digging. He scrambled to his feet. "Is that.." he inched forwards and caught sight of a dog's skull under a flap of blanket. He turned away with a cry. "Oh God Argos! I completely forgot—" Steve dropped the shovel, grabbed Arix and dragged him backwards, away from the edge of the cliff.
"Careful."
"I killed him!"
"Calm down." Arix paced, whimpering. "It's just a dog."
"It wasn't just a dog, he was your only companion out here." Steve looked at the ground and the muscles worked in his neck.
"Don't worry about it too much," he said after a moment. Arix looked towards the blanket and froze, the back of his neck prickling. Something was moving under the blanket. A dog stood up, swaying on stick legs, charred to the bone. Its black eyes bored into him, glittering, black like deep caves, the black of eyes taken by the Corruption. It crouched and raced forward, leaping at his throat, and he stumbled backwards with a scream. His feet fell on air. Then he was dropping backwards over the cliff, watching Steve shrink away above him. There was an almighty thump. Then stillness.

Steve looked from Arix, sprawled on the forest floor far below, to the pile of dry bones under the blanket. A hollow laugh came from the unfallen half of the treehouse. He looked up. Herobrine was sitting in the burned frame, legs dangling over the edge. "What did you do?!"
"Illusion. Quite easy, given his present state."
"Why would you..."
"It was too good not to. Did you see his face?"
Steve looked stonily at him. "I did."
A board cracked, and Herobrine teleported to the ground before it could fall. "Does it bother you? After all, he did burn your house down. I'd expect you to be angry."
"I don't care who burned my house down. What I care about is that you just made Arix jump off a cliff."
"Oh, you don't? That's good, because I did, actually. Knocked some coals out of the fire. I thought it would make things more interesting. Although it is rather Arix's fault anyway, for making the fire in the first place."
Steve shook his head. "Why?"
"Why not?"
"Because it's petty. I expected more of you, alright? All this time of you hunting me and torturing I thought, well, he has some reason to be angry. And as long as you enjoyed being evil maybe it wasn't so bad. I thought you were off accomplishing great things, burning cities and slaying giants, but no, you're throwing illusions at people who are already insane and starting forest fires just to watch the trees burn up. Why would you do that?"
Herobrine sighed loudly. "There's only so much to be done here, Steve. Are you going to check on your friend? I believe he's dead, but perhaps not, after all he survived the fall before."
"Did he?" Steve rushed to the edge. Arix still hadn't moved. He started to climb down. Herobrine appeared below him with a white flash. Steve moved faster.
"He's not dead at all," marveled Herobrine, sitting Arix up. Arix supported his own weight without moving, staring straight ahead. "But he's gone nonresponsive." he snapped his fingers in Arix's face, then slapped him lightly.
"Don't you dare," said Steve, jumping to the ground. Herobrine slapped Arix harder. His head snapped to one side. Otherwise, he made no movement.
"Totally out of it," said Herobrine. Then something crashed into him.

In two hundred years, Steve had never attacked him. He'd tried once or twice. It had always ended with him cowering in a corner or fleeing in a blind panic while Herobrine laughed. So he wasn't prepared. This must have been why Steve was able to grab him, sling him off his feet and beat him against the cliff wall and the ground several times before pinning him down by the neck. "Don't you fucking dare." Herobrine looked up at Steve's face in bewilderment. He hadn't expected Steve's angry face to look so terrifying. He'd forgotten—if, actually, he had ever known—that Steve had an angry face. Then he realized that he was about to black out and he didn't have time to teleport. He felt a new kind of rage, a rage tempered with fear. He struck out, but already darkness was falling.

Steve dragged Herobrine to the nearest tree, took out some strands of spider silk and tied him. A wooden object wrapped with a cord around his wrist was in the way. Steve tore it off and threw it without looking at it, and it fell in the stream and drifted away. Steve finally stumbled back to examine his handiwork. Spider silk blocked teleportation. Herobrine could easily burn his way out, of course, but it would hold him for a while. Was he waking up? Steve choked him again, careful to leave him just at the point of death. He didn't want him respawning and waking up. He wanted him dead to the world for a while. Then he walked over to Arix and knelt in front of him, realizing on the way how hard his heart was pounding. "Arix." nothing. "He's gone. You're alright." nothing. Steve picked him up and gasped as Arix's shirt rubbed against his chest. Looking down he noticed the livid burns where Herobrine's fingers had raked across his chest. He started walking. It took only a few moments to finish burying Argos and climb onto the skeleton horse with Arix in front of him. Fortune was waiting at the edge of the forest. He stopped briefly to juggle saddlebags—he didn't want to overburden the skeleton horse, but Fortune had saddle sores which he didn't want to agitate, either. Then they rode into the night.

A/N: Well, Argos survived longer than his namesake. The dog in the Odyssey dies pretty much the second after he's mentioned. The narrative is like "Oh look a dog! Now it's dead."
Trivia time: Endermen cannot teleport while stuck in a cobweb. I do have a basis for the "spider silk stops teleportation" thing.
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