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They told Sonic that he would have to make a choice. Destroy Enerjak, or let it destroy the world. Sonic thought that was bull.
He hadn’t had a choice in any of this. He didn’t choose for his brother to meet the world’s most obviously villainous echidna. Didn’t choose for him to get tricked and possessed (possessed, not killed, Sonic refused to believe Knuckles would die in such a (horrific) lame way). He didn’t choose for his possessed (not dead!) brother to go on a rampage. He definitely didn’t choose for G.U.N. to get involved.
They’d taken the Master Emerald ‘for safe keeping’. And Mom and Dad just let them. Like Knuckles wasn’t gonna flip when he got back. And now G.U.N. had turned around and asked Sonic for help protecting it.
G.U.N. also had Finitevus, though they weren’t protecting him as much as imprisoning him. That’s how they’d learned Enerjak’s name. Apparently the thing that had taken control of Knuckles was supposed to be some kind of evil demi-god who the echidnas occasionally whipped out like a superweapon to save their butts. Why they hadn’t called on it when they were nearly extinct was unclear. According to Finitevus, they’d never lost the knowledge of how to do it, they just… never used it. Sonic’s theory was that echidnas don’t like to have their butts saved. Regardless, they hadn’t summoned the Enerjak since they lost the Master Emerald. Which was especially weird considering:
The Enerjak was drawn to powerful things like moths to bright lights. It knew where the Master Emerald was and it was coming for it. But like… kind of slowly. It didn't have a ton of purpose, this Enerjak. Which was weird. It was wearing Knuckles like its personal skin suit, but it didn’t have Knuckles’ drive. It was aimless. It got sidetracked destroying things and crushing G.U.N.’s tanks like empty soda cans. Which might have been almost cool if it wasn't… y’know, wearing his brother like its personal skin suit .
Again, Finitevus provided answers. Enerjak was supposed to help the echidna people. There were none. It was a weapon without a guidance system and it was going off indiscriminately, but in the general direction of the Master Emerald.
The concern was what would happen once it got ahold of it. With that much power, the Enerjak would be even more supercharged than it already was–that was world-ending power. They needed world-ending power to counter it. Which is how Sonic found out that G.U.N. also had the Chaos Emeralds.
Only Sonic had proven that he could keep control of himself while using all seven Chaos Emeralds. No one else could counter Enerjak. That was when the choice was laid out before him: Zap Enerjak into oblivion (and Knuckles with it) or let Enerjak continue rampaging. And now? Now it was decision time.
“He’s in the compound!” Tails’ voice sounded both in Sonic’s earpiece and from down the hall. His brother rounded the corner, eyes wide and tail fluffed. He pressed a few buttons on a panel behind him and a massive steel door came down, blocking the vault’s only entrance.
“They’re trying to hold him back but–”
“They won’t be able to keep that up long,” Sonic finished for him. He looked behind him at where the Master Emerald floated, suspended inside an energy cage. The Chaos Emeralds sat each in their own energy cage in a circle around the Emerald. Or at least, they had. Now they were all laid out on the control panel in front of Sonic.
The two of them stared at the gleaming gems for a few moments. Outside, explosions shook the building. Dust rained down from the ceiling. Shots rang out. But it never seemed to matter what they threw at it, Enerjak would just get back up again.
“What are we going to do?” Tails asked.
He meant what was Sonic going to do. Nobody else had to make this choice.
Sonic raised his hand and paused. Did he really want to do this? Did he even really have a choice? He reached for the Emeralds. His hand hovered over them, lingering.
The wall exploded beside them.
From the cloud of dust, it emerged. It paused, distracted by the two of them.
Sonic put himself between it and Tails, then stopped. “Oh, Knuckles,” he said.
Knuckles’ body was riddled with bullet holes. His face was a mess of blood. Sonic couldn’t even say what was intact and what wasn’t. His side was shredded, shrapnel still sticking out of him. Only a few bloody tatters remained of his left arm. But there was an evil, echidna, war god inside him, so despite all the insides leaking to his outsides, Knuckles’ body was still standing.
For a moment, Sonic thought his decision was made. He would use the Chaos Emeralds and destroy Enerjak. Because there was no way Knuckles could still be alive with his body like that. He was gone. This thing was just wearing his body like a hermit crab in a messed-up shell. And Sonic wasn’t going to let it do that to his brother.
But then it was like something rippled under its skin. Bullets started dropping out of him. A bone jutted out of his shredded shoulder. Red fibers crawled down like spiderwebs while two more bones formed. Tails shudder behind him. Sonic couldn’t look away. The tatters of Knuckles’ arm writhed as they returned to their places. Boney fingers flexed. Skin stretched. Fur grew. The bloody mess that was his face started to look like a face messy with blood.
In a moment, Knuckles’ body was whole again. And Sonic was left in doubt once more. Because maybe Knuckles could be saved. He had a body to come back to afterall.
While Sonic was torn, Enerjak had made up its mind. It turned away from the two stationary targets, toward the Master Emerald. The giant gem seemed to softly flare for a second. It felt, to Sonic, like a hesitant wave.
“You…” Enerjak’s voice sounded like Knuckles’, but with something laid over it. Something old and echoey. It lurched toward the Master Emerald, moving like Knuckles was an outfit that didn’t fit quite right.
“Sonic!” Tails gasped.
Sonic stepped back, pushing Tails too. It stalked past them. Past the Chaos Emeralds. It had its eyes on a bigger prize.
“Sonic, what are you going to do?”
Sonic looked at the Chaos Emeralds. He knew what he had to do. He reached for them. But … his hand just wouldn’t move.
Enerjak tried to reach for the Master Emerald, only to get zapped by the energy cage. It snarled and punched the cage. The cage held. But it wouldn’t for long.
“Sonic?!”
Sonic looked behind him at Tails’ fearful eyes. What if it was Tails? What if it was Dad? Or Mom? Knuckles was a knucklehead, but he was Sonic’s brother. Could Sonic do this to his brother? To save the world?
Enerjak struck the cage again. The lights flickered and the energy field warbled, its outline shaking ominously.
Tails didn’t call Sonic’s name again, just squeezed his arm.
Sonic lowered his hand, away from the emeralds. He offered Tails an apologetic smile. “I can’t do it.”
Tails looked shocked and then… understanding.
Sonic turned and watched as Enerjak wheeled back for a third strike. As much as Sonic wanted to be the guy who saved the world, he didn’t want to be the guy who sacrificed the people he cared about. “I’ll save the world some other way,” he promised.
Enerjak brought Knuckles’ fist down on the cage a third time. The energy field exploded. The lights died. Red, emergency lights kicked on in a moment, illuminating Enerjak as it put its hands around the Master Emerald.
The room was bathed in a brilliant, green light. Tails flinched back behind him. Sonic didn’t know what was going to happen–but it would probably be bad. He needed to get Tails to safety.
“C’mon–” He turned to urge Tails to go.
“No!” Enerjak roared.
They both froze, heads whipping around to look at it in shock. Sonic’s heart picked up speed. Was it just his imagination, or had its voice sounded more like Knuckles’ just then?
Enerjak wasn’t even looking at them. It was holding the Master Emerald. Why wasn’t it absorbing it? Enerjak thrashed and snarled. Green electricity arced across Enerjak’s hands. It became more frantic, spitting and writhing like a trapped cat. It wasn’t holding the Master Emerald. It was holding him.
“I… I think,” Sonic said. “Maybe it’s healing him?”
A strange wind seemed to rise out of nowhere, ruffling Sonic’s ears and Tails’ fur. The dust that had begun to settle was kicked up again. The Emerald flared and the wind grew faster and stronger. It felt almost as if it was pulling on Sonic. He had to brace, keeping one hand out to grab for Tails. They both flinched as grit and small rubble flew past them. It was getting harder to see Enerjak, but the shining emerald ensured that they could still see his outline.
Another flash of green light. Electricity jumped up Enerjak’s arms. Enerjak screamed . At first it sounded like Knuckles, but as the wind whipping around the Master Emerald became more and more intense the sound began to change. The mini-maelstrom was growing larger, filling the whole room. Sonic and Tails were forced backwards, only able to watch as pieces flaked off of Knuckles. It was like he was made of sand and the wind was slowly blowing him away.
“Crap!” Sonic yelped. “Maybe it’s not healing him!” Maybe it was killing him!
He ran into the fray. Tails called after him, but his voice was lost to the wind. Sonic didn’t know what he was going to do, but he had to get the Master Emerald away from Enerjak.
The wind threatened to take him off his feet. He tried for a moment to run against it. He was faster than the wind, but it was stronger. There was another green pulse and Sonic was lifted off his feet.
He tucked and rolled. Going against the wind was a no go. As soon as he hit the ground he uncurled and ran with the wind, leaning in. He had to run around the room a few times, but each turn brought him closer to the center of the gale.
Sonic broke through and was disappointed to find there wasn’t really an eye to this storm. There was just a slightly less windy and dusty area.
Enerjak was close now. He was still howling, his arms all but disappeared in the arcs of electricity coiling off the Master Emerald. The emerald itself was impossibly bright, Sonic couldn’t look directly at it. But he needed to get it away from Enerjak before it destroyed Knuckles.
He dashed up to them, bracing against a burst of wind. Enerjak was still screaming, but this close it seemed to almost be coming from outside of his body. It was coming from outside his body. Knuckles’ body was arched, his eyes wide, jaw flexing.
“I don’t want you,” he rasped.
“Knuckles?” Sonic asked. He dared to touch one of his arms. The Master Emerald’s electricity passed harmlessly over his hand. “Knuckles, can you hear me? I’m here. It’s going to be okay!”
He reached for the Master Emerald, but he was unable to lay a hand on it. It wasn’t like with the Chaos Emeralds. This wasn’t a mental barrier–he literally couldn’t touch it. The Master Emerald wouldn’t let him. He pressed against Knuckles to brace himself and pushed with all his might, but his hands could not get any closer.
“Knuckles! You have to drop the rock!” He urged. “I’m going to save you, but you have to help–”
“I want you OUT!” Knuckles screamed.
Sonic flinched as the Master Emerald flared again. Spots cleared from his vision just in time to see Knuckles’ shape collapse. His body blew apart like a blown out candle. Sonic stumbled and fell to his knees as the body he was braced against suddenly vanished.
Enerjak was still screaming. Sonic lifted his head, watching in numb shock as the wind picked up speed, carrying away the ashes that once were Knuckles. Enerjak’s voice howled around and around, growing louder and louder and sounding less and less like a person.
And then it just stopped. The sound echoed for a few seconds longer as the roar of the winds died down. The Emerald’s glow faded.
Dust hung heavy in the air. Sonic heard a cough and Tails’ shape emerged from the murk.
“Sonic?” He choked. “Where’s Knuckles?”
Sonic turned to look behind him at the Master Emerald. It floated unassisted, its light calm as one ribbon of wind wound slowly around it. Dark particles shifted around in circles, some sparkling green. The wind coiled tighter and shorter until the dust began to pile together, slowly forming a shape.
The Master Emerald flashed one final time, a blinding light that forced them to look away one last time. And when the light faded they looked up to see: beneath the Master Emerald lay a single egg.