"Pretzel!" Whip called, cupping his hands around his mouth. "PRET-ZEL!" Drawing out the syllables didn't make a difference. There was no sign of his sister.

There was no sign of anything. His current cavern was dark, as all of the caverns had been. The air was thick with the strange shadow fog, and glowing purple crystals decorated the walls, floor, and ceiling, their light pulsing like a heartbeat. It made Whip imagine being inside a giant creature, the crystals its veins pumping glowing blood. Maybe that wasn't far from the truth. Something had happened with the big monster in Apotos; had it eaten him like it had eaten Pretzel? He'd figure it out when he found her. Pretzel was smart; she'd know what was going on.

Still, the cave was creepy. It wasn't covered in ice, like Midnight's cave, and it wasn't all wet and slimy, like Hurricane's (though it did have a stream running down the floor he could hear burbling in the darkness), but it somehow seemed more… hostile than both. The stalagmites and stalactites (he could never remember which was which) jutted into teeth-like points, all aimed directly at him. The crystals, too, jabbed into the air like fangs, and the shadows drew much closer to him than they had before, even with his ball of light. They almost seemed like creatures, wolves darting in to nip at his heels before retreating from the light. He imagined them circling just outside his vision, hidden by the darkness. Watching. Waiting. Testing.

Something scraped on the floor and Whip spun around. Was that a pair of glowing eyes?

You're just imagining things, Whip told himself. You're safe. Perfectly safe. That was what Amy always said whenever he had trouble falling asleep after seeing something scary on TV. Except this wasn't Amy's apartment, and it wasn't his safe, cozy bed. This was a strange cave, or maybe the belly of a giant monster. He had no idea what to expect here. And there was no Amy to protect him.

Another scrape on the stone—he was sure that was the click of claws—and Whip whirled around again, backing towards the reassuringly steady sound of the stream. Would the monsters be able to swim?

As Whip's heart rate increased, the shadows seemed to respond to his fear, drawing closer to the circle of light. He wasn't imagining things. He could see them now, creatures in the darkness. They looked like aliens or horror movie monsters, not real animals. Like Hurricane and Midnight, they were reptilian, with dark, smooth skin and glowing markings. But where Midnight and Hurricane had seemed one-of-a-kind, there were a countless number of these things. Some looked like bees, flying in the air with glowing, spear-like stingers; some were weird hovering sphere creatures; some looked like eyeballs, and some like lizards, and some like wizards, and some like dinosaurs. None of them had the gleam of intelligence in their eyes that Midnight and even Hurricane did. They seemed… mindless. If Midnight and Hurricane were bosses, these were clearly the basic minions.

A lot of basic minions.

"H-hi," Whip squeaked, clutching his ball of light close. "Um. Nice to meet you?"

One of the lizards lunged for him with a screech. Whip screeched back and stumbled away. His paw hit the water and he slipped into the stream, the light ball falling from his hands. The water was freezing. The temperature didn't bother the lizard thing; it jumped right in after him, and its brethren followed. Whip rolled away from its slashing claws and splashed through the stream, away from the creatures.

The light ball, drifting downstream on its own, dissipated in a puff of light that flew right to Whip's chest. A brief surge of warmth, and then he was left alone in the dark. He glanced over his shoulder. He glimpsed the glow of the monsters's markings, rapidly drawing closer, and he could hear the cacophony of their shrieks and snarls. He missed when the only sound had been the stream.

Whip tried to will another ball of light into his hands, but it was hard to think past the panic and the fast approaching monsters. He nearly tripped in the stream again before he remembered he had wings and took to the air. Unfortunately, the cave's ceiling was low, too low for him to fly well. At least he was going faster now. Maybe he could outrun the monsters.

A blue glow in front of him. In front of him? Whip stopped in the air, glancing back. No, he hadn't gotten turned around; the pack of dark creatures were still behind him, fast approaching. And now there were more dark creatures in front of him. Whip swallowed and balled his hands into fists. He'd have to fight.

The first lizard-thing reached him and leapt into the air. Whip yelped and darted away, but another creature jumped for him, and another, until there was nowhere to run and one of them finally pulled him to the ground. It pinned him there, hissing victoriously while Whip struggled to push its—thankfully blunt—claws away from his face. Its touch was cold, though not as bad as the Apotos monster. The other lizards crowded around, shrieking and trying to dart in and bite at him. They weren't working together, which was lucky, but in their eagerness they'd probably trample him by accident. Whip writhed, trying to push the first lizard's claws off him, but it hardly seemed to notice as it hissed at the others. Were they fighting over him? Were they planning to eat him?

Come on, Whip told himself, trying to summon up his light like he had when Nova attacked Pretzel. Do something! But the light felt a lot harder to reach when he was pinned on his back, surrounded by the dark and the cold, alone. He scrunched into a ball as best he could with the creature pinning him and squeezed his eyes shut. Somebody, please, help me!

The lizard creature screamed, and suddenly the weight was off Whip's chest. He blinked his eyes open to see a new creature standing over him, snarling. It looked like a wolf—or, no, like the shadow of a wolf. Whip flinched, but the wolf wasn't growling at him. The shadow monsters backed away, hissing to each other—confused? The wolf did not explain itself; it snapped Whip up in its jaws, leapt over the monsters' heads, and took off running. Whip yelped and wriggled, trying to get himself free or at least in a more comfortable position. Hanging by his scruff from the jaws of a shadow wolf was not an ideal way to travel. But the wolf didn't stop. It just ran and ran, until the angry baying of the monsters had faded into a distant echo, and once again the only sound was the trickling of the stream.

At last the wolf set Whip down. He scrambled to his feet and backed away, but the wolf didn't attack. It just stood there, watching him.

It didn't look like the monsters had. It was pure black, but it didn't have scales or smooth skin like the other monsters. It looked as immaterial as the shadows wafting over the cave floor, but it had somehow carried Whip away with very physical jaws. He couldn't make its mouth out now that it was closed, or its eyes for that matter. It was more of a silhouette than an actual creature. Yet it had saved him. Was it another fragment?

"Who are you?" Whip asked curiously.

He hadn't really expected an answer, but to his surprise the wolf shifted, its shadowy form twisting and reshaping itself into a more person-like shape. Then it solidified, real features forming out of the dark mass, and at last a Mobian wolf stood before him. It—he—was shorter than Amy or Sonic, though that was still twice as tall as Whip. His fur was still black, but now it had a slight purple hue, though that might have just been from the glow of the crystals. His muzzle and paws were dark grey, and he had pale blue-grey fur on his chest, wrists, ankles, and the tip of his tail. Glowing purple markings lined his arms, legs, and eyes, and speckled his muzzle. A crescent moon glowed on his forehead. His eyes were a cool green.

"My name's Black," the wolf said. His voice was low and soft, with the same rough, growly edge as Pretzel's.

"You're not like the other fragments," Whip said.

Black had a lot of the same features as all Dark Gaia's fragments—dark colors, glowing markings, sleek shape (though in this case that shape was covered by fur, not scales). But none of them, not even Pretzel, looked as distinctly Mobian as this one. Pretzel looked a little like a cat and a little like a bat and a little like a snake and mostly like nothing else at all. Midnight and Hurricane and even Twist had been the same way. But this new fragment was clearly a wolf, the same way Amy was a hedgehog and Big was a cat and Knuckles was an echidna. And his eyes… all the other Dark Gaia fragments, even the monsters that had just been attacking him, had mostly black eyes with glowing pupils. Yet this one's eyes looked perfectly normal. Green, like Pretzel's. And like…

"You look kinda like Sonic," Whip realized, cocking his head. He couldn't say why; Black was shorter than Sonic, and stockier, and he was a wolf, not a hedgehog. Maybe it was just the way the fur on his head spiked a little like quills, or maybe it was the green eyes. But the thought nibbled at him, persistent. "Are you related to him?"

"Yes," Black said. "Same as you."

Whip frowned. "I'm not related to Sonic. We aren't even the same species."

"Relationships shape us," Black said, and started walking away, as if that was an explanation.

Whip hurried after him. "But that doesn't make us related. To be related you have to have, like, the same parents. Or your parents have the same parents. Or something like that." He looked down at his feet. "Gaias don't have parents, so I'm not related to anyone."

There was silence for a moment. Then, Black spoke: "You aren't Light Gaia."

Whip's head snapped up to stare at Black, but the wolf wasn't looking at him, gaze fixed steadily ahead. "What?"

"You aren't Light Gaia. Not anymore. You've known others, and they've changed you." He finally looked down and met Whip's gaze. "Her as well. You've both changed."

That sense of familiarity tugged at him again. Green eyes… "Who are you?" Whip demanded. "You aren't like the other fragments. You're something different."

Black smiled softly, an expression at once fond and sad. "I'm just another cast shadow."

Whip frowned, but Black didn't elaborate further. He didn't seem likely to answer more questions about himself, so Whip decided to try something else. "Do you know where Pretzel is? I've been looking for her."

"Why?" Black asked, looking at him sharply.

Whip flinched away, even though Black hadn't moved to attack him. His ears had turned back, and his eyes seemed steely, like they might stab Whip just by looking at him.

Whip swallowed under the force of that glare, but he pressed on. "Because—because whatever she did, before, when we were…" He took a breath. "Because whatever happened before, she's my sister now, and I want to help her."

"And what does she want?"

Whip blinked. "Um. To not be swallowed by a giant monster?"

He thought he saw a hint of a smile before Black's expression became serious once more. "Maybe. But what if she doesn't want your help?"

Whip frowned. "Why wouldn't she want help?"

"Many reasons," Black sighed. "All I'm saying is she might not be happy to see you."

Whip swallowed, remembering Pretzel running from him in the first cave. But then he thought of her back in Apotos, huddled alone in an alley as the darkness swallowed her. He'd abandoned her once. He wouldn't do it again. If she didn't want his help, she could tell him herself. And if she really wanted nothing more to do with him… he'd just have to live with that.

"I understand," he told Black. "I still want to find her."

Black studied him as if searching for something. Whip waited, not looking away. At last Black nodded and turned forward again. "I'll take you to her."

"Really?" Whip gasped excitedly.

Black nodded, not looking nearly as excited as Whip. He didn't speak further, and all Whip's attempts at conversation were met with noncommittal grunts until finally he gave up. The tunnel they walked down only got darker, the shadows thicker, the rocks more jagged, like fangs or spears pointed toward them. Warning them away. Black's words echoed in Whip's head. She might not be happy to see you.

A few times they spotted a pack of monsters ahead, forcing Black to change course and take them down another tunnel. Usually they could avoid the monsters easily, but if they accidentally got too close they seemed to sense Whip, and even if they couldn't see where he was, they'd work themselves into a frenzy trying to get to him. In those cases Black would melt back into the form of the wolf and distract them until Whip had gotten far enough away. The monsters didn't have the same interest in Black as they did in Whip. Maybe they saw him as one of them.

Black did seem to have a connection to… whatever this place was. He always knew exactly which tunnel to take, and which detours would avoid monsters while still moving them towards their main destination—that destination being down, judging by the way the tunnels sloped. Their passage only got darker, too; in a few places there were no glowing crystals at all and Black—apparently unaffected by the lack of light—had to lead Whip by the hand. As they clambered down increasingly steep tunnels, surrounded by stones like teeth and a darkness never touched by the sun, the feeling of being swallowed by a vast beast only grew stronger.

"How do you know where Pretzel is?" Whip finally thought to ask Black. He didn't think the wolf was misleading him, but that didn't mean he wouldn't get lost by accident. You could look confident and still have no idea what you were doing; Whip knew that from experience.

Black looked down at him, his markings glowing a soft blue-purple. "I'm part of this place. And her."

Whip looked around at the cave. "Is this place why I can't feel her anymore?"

He'd tried prodding at their bond without results. It wasn't something he'd ever questioned, that link. Sensing where Pretzel was, getting impressions of her thoughts and emotions, always feeling like she was right there, like they were connected even when she was a block away… that had all seemed perfectly natural to Whip. Only now did he realize it was probably a Gaia thing and not a regular sibling thing. And only now, when he reached out for Pretzel and found only stone walls, did he realize how much he'd taken it for granted.

"Maybe. She doesn't want you to find her." Black's expression darkened. "None of her does."

"Hurricane and Midnight do. And you do, too."

Black smiled at him. "That's true. But even we…" he shook his head. "It's frightening."

Whip's ears flattened. "You're frightened of me?"

"Of what you were," Black said frankly. "What you could be again. But…" he glanced around at the tunnel. It wasn't just the pointed stones or the darkness; the very air had a weight of hostility to it. "You've changed. And she needs you."

Black stopped suddenly, and Whip looked around, expecting more monsters. All he saw were the glowing crystals—they seemed concentrated here, clustering across the walls and peppering the ground so there was barely any bare stone left. Yet their combined glow hardly combatted the thick shadows, which had grown so thick Whip was sure he could feel resistance when he moved through them, like he was wading through water.

"We're here," Black said, nodding toward the opening in the wall ahead.

It was too dark for him to see what was on the other side; in fact, the shadows seemed to be pouring out of the cave ahead. Crystals circled the entrance, pointing out like teeth, and frost slicked the stone around them. It did not give the impression of a warm welcome. Whip glanced up at Black hopefully, but he shook his head, expression grave. Whip would be taking these last steps alone.

"Good luck," Black said softly.

"Thanks," Whip whispered. He swallowed his fear and stepped into the dark.