The maintenance tunnels were to the underground what chutes were to the rest of Metru Nui: a quick means of transport from one end of the city to the other. Unlike chutes, which served everyone in Metru Nui, the tunnels were open only to those with authorization, normally Ta-Matoran and Onu-Matoran. Pipes big and small lined the walls of the tunnels, funneling liquid protodermis from place to place and molten protodermis to those locations that required extra heat.

Ordinarily, Matoran traveled through these tunnels by cart. But Matoran carts were too small for Toa Metru. Whenua idly wondered if the Toa should see about getting vehicles made for them in the future. It might save a lot of walking, swinging, and climbing.

The Toa of Earth felt uneasy. He knew the other Toa Metru were expecting him to take the lead on this mission, but his knowledge of the Fikou web was based largely on stories he had heard. He had never had cause to go much farther than the very outer edges of the tunnel network, and even that was with reluctance.

He was still worrying over this when he felt a cold breeze rush past him. It had come from deep in the maze, which made no sense—there should have been no openings to the outside up ahead. The only hatchways led up to the Archives, and certainly no breeze could come from there.

None of the other Toa seemed particularly disturbed by the strange wind or the drop in temperature. Whenua guessed they just didn't grasp the strangeness of the situation. He suddenly felt as if he could not take another step forward. Something was waiting up ahead, something far worse than any crack in the seawall, and they were walking right into its jaws. He just knew it.

His suspicions were confirmed a few moments later when a thick fog sprang from nowhere to engulf the Toa. Even their lightstones were of little use in penetrating the cloud. Whenua turned to find he could not make out any of his companions.

"Vakama? Nuju? Are you there?" he called out.

"Yes. What is this?" Vakama replied.

"l have never seen fog like this, not even in Ga-Metru," Nokama's voice added. "It is unnatural."

Just how unnatural it was became painfully obvious. A sudden flash of light almost blinded the Toa. An instant later, an impact sent Whenua crashing into his friends. Barely clinging to consciousness, the Toa of Earth said, "What in the name of Mata Nui was that?"

"A lightning bolt," answered Onewa. "A lightning bolt in an enclosed tunnel underground. Is this normal in Onu-Metru, or are we just lucky?"

As if the freak storm had heard him, a second bolt flew toward the Toa of Stone. Acting on reflex, Onewa dove to the side as the bolt struck the wall where he had been.

"That was no accident," said Nokama. "Perhaps it's time we turned back and planned a strategy."

Nuju's voice broke through the fog. "If we could see where we are going, I would agree. As it is, I don't think we should turn our backs on an angry thundercloud."

"Quiet!" said Vakama. "Listen!"

The Toa Metru went silent. Now the air was filled with an ominous buzzing sound, which drew closer and closer. Not being able to see what caused it made it all the more frightening. "All right, keep calm," said Vakama. "Remember that we are Toa Metru, and we are together. As long as we stay united, we can overcome anything."

Privately, Vakama was not feeling quite so confident. He thought he recognized that sound. If he was right, it came from a breed of Ta-Metru winged insects, nicknamed 'fireflyers.' Left alone, the small insects were relatively harmless. But when a swarm was angered, they would pursue an enemy halfway across the city, and they possessed a fiery sting. They were known to nest in furnaces and in the ground tunnels beneath the Metru, but this still seemed too deep for them.

Behind him, Matau had finally had enough. Bad enough to be wandering underground without all this danger and confusion. He raised his aero slicers and summoned a wind to blow the fog away. Even though his powers were still weakened from the fight with the Morbuzakh, and the best he could manage was a stiff breeze, it was still enough to get the job done.

The fog dissipated, to reveal a sight out of every Matoran's nightmare: two powerful, menacing creatures, reptilian-like heads darting back and forth, staffs held tightly in their claws.

"Rahkshi!" shouted Whenua.

One of the Rahkshi was gold in color and now it screeched at the Toa. This Rahkshi had the ability to manipulate the weather within a limited range. Its partner, bright orange in color, was surrounded by a swarm of fireflyers. Controlled by the Rahkshi, the insects were just waiting for the signal to charge.

"What are they doing here?" asked Nokama.

"A better question is, what are we doing here?" said Onewa. "It took three squads of Vahki Zadakh to stop one Rahkshi that appeared in Po-Metru, and even then all they could do was drive the thing away."

"Then we will have to do better," said Nuju, blasting ice out of his crystal spikes. But his powers were not what they had been before the clash with the Morbuzakh, and the Rahkshi shrugged off the cold. The gold one hissed and unleashed a blizzard in the direction of the Toa.

Battered by wind and ice, the heroes fell back. Only Vakama saw the advantage they had gained—the intense cold was felling the fireflyers one by one. Angered, the orange Rahkshi was now advancing on the gold one.

Now the Toa were witness to a scene of complete chaos. The gold Rahkshi had summoned another storm and was hurling lightning bolt after lightning bolt at its insect-controlling cousin. What it did not realize was that a swarm of tiny devourers was pouring forth from every crack in the walls and floors. Devourers would consume any bit of inorganic protodermis they ran across. Rahkshi armor was definitely on their menu—and all of them were hungry.

"This would be really entertaining if we didn't have to get past them to go on," said Onewa. "Whenua, you're the librarian, what do you know about these things?"

The Toa of Earth had by now shaken off the lightning strike and regained his feet. "Rahkshi are very territorial and quick to anger. If we make a move toward them, they'll forget their own fight and turn on us again."

"But this isn't about us, is it?" said Nokama. "They have claimed this portion of tunnel as their own and they are defending it."

"Then that is the answer," said Nuju. "We make it not worth the effort to defend. Vakama, Whenua, I will need your help."

Nuju outlined his plan in as few words as possible. The Rahkshi's clash was becoming even wilder, threatening to bring the tunnel down around them. When the Toa of Ice nodded his head, Vakama placed his palms on the floor and sent waves of scorching heat through the stone. Meanwhile, Nuju used the remains of his elemental power to create icicles on the roof of the tunnel.

Just as the Rahkshi took notice of the heat underfoot, Whenua went to work with his earthshock drills. Driving them into the ground, he formed a crevasse that ran straight toward the Rahkshi. Both of the creatures had figured out the Toa were somehow responsible for the sudden change in conditions, and they were not happy about it.

Nuju's plan had worked halfway. The Rahkshi were definitely uncomfortable, but not rattled enough to flee from their chosen home. Vakama loaded a disk in his launcher and hurled it through the air at the gold Rahkshi. When it struck, the enlarging power invested in the disk caused the Rahkshi to shoot up rapidly, smashing its head into the ceiling and bringing icicles raining down.

The insect-controlling Rahkshi did not react as Vakama hoped. Instead of fleeing into the darkness of the tunnels, it charged forward toward the Toa. Nokama and Vakama reacted as one, he launching fire and she water at the oncoming creature. But when their energy streams collided, the result was a wall of steam. By the time the cloud cleared away, the Rahkshi was nowhere to be seen.

"Somehow I don't think a steam bath frightened it away," said Nuju. "It will be back."

"Mata Nui! Why don't you watch what you're doing?" Nokama snapped at the Toa of Fire. "I might have stopped it if you hadn't gotten in the way."

"l got in the way? That wasn't how it looked from here," Vakama answered.

Nokama was about to say something else when she changed her mind. Arguing wasn't going to make anything better. "I'm sorry, Vakama. Neither of us was at fault. But this is exactly why I have been saying we need leadership. We cannot keep blundering through challenges without any strategy."

"Here's a strategy," said Onewa. "Let's stop talking and start moving, before we get any more surprises."

The Toa Metru resumed their journey into the tunnels. None of them noticed another pair of eyes watching them, eyes far more observant than any Rahkshi's could be. They noted the way each Toa moved and fought, filing the information away for later use. Then the owner of those eyes slipped away into the darkness without making a sound.

The hunt had begun.

X X X

The Toa Metru did not encounter any more difficulties as they penetrated the outer edges of the maintenance tunnels. Now and then a small Rahi would skitter across their path, only to vanish down a hole or among the pipes. As they moved deeper into the maze, the air grew increasingly stale. Matau wondered aloud how Onu-Matoran could stand to work down here.

"Practice," said Whenua. "Most Onu-Matoran start out as miners, digging for lightstones. You get used to the dark pretty quickly. If you're lucky, you get the opportunity to become an archivist, but even then you are indoors and underground much of the time. These tunnels might be a little extreme, but nothing an Onu-Matoran can't handle."

Onewa looked around. "l don't see any Matoran though."

"Well…see…some of the ones who have come down here in the past sort of…haven't come back."

"You said that was a legend," said Nokama.

"Evidently, Onu-Matoran legend has a basis in fact," muttered Nuju.

"Anything else you forgot to tell us, Whenua?" asked Onewa.

Whenua raised his lightstone to give the Toa a good look at what lay ahead. "Just that." The wide tunnel they were walking through came to an abrupt end at a stone wall a few paces away. Six narrow openings were visible in the wall, barely more than slits in the rock. "This is the start of the Fikou Web," said Whenua. "From here, it's just narrow tunnels drilled into the rock, crisscrossing with each other, until we reach the main tunnel on the other side."

"Do we split up?" asked Vakama.

Whenua nodded. "The major crack in the seawall is on the other side of the web, but there could be damage closer to us as well. Each of us should take a tunnel. We'll see each other as we go, I'm sure, and then we can all meet up on the other side. Hang on to your lightstones. If you lose them, you might become a permanent resident down here."

"That's what I like about Onu-Matoran," said Matau. "They are always so full of happy-cheer."

X X X

The gold Rahkshi moved carefully down the tunnel. Every one of its senses was on the alert. There were still intruders in its territory, and that was very bad. Intruders made loud noises and tried to drive the Rahkshi away, unless the Rahkshi struck first.

It could not hear the six from before, but it could smell them. They were no longer together and their scent carried traces of fear. That was pleasing to the Rahkshi. When the ones from up above carried fear into the tunnels, they were easier to find and easier to drive off.

The Rahkshi tried hard to remember how it had come to live in this place. But it could not. It had a vague memory of once living someplace else, then a long journey to the land above. But there were too many others there who tried to capture it. The Rahkshi escaped and fled down, down into the cold, welcoming dark.

The creature paused as it sensed another presence up ahead. Another Rahkshi, but not a threat. It stayed close to the wall as it moved forward until the other came into view. It was the orange Rahkshi from before, but now it was stretched out on the ground and not moving.

The gold Rahkshi crept closer. Why was the other so still? Was it hurt? Had the cold sleep overtaken it? No, the wormlike kraata inside was only stunned. Still, it wondered what could strike down a Rahkshi like this. Not one of the little ones from above. Not one of the six.

Wait! There was a scent in the air, strong and not unfamiliar to the Rahkshi. It had encountered a creature before with this scent, long ago when it first came to the tunnels. It sifted through dim memories trying to bring the image of the creature into focus.

Then suddenly the Rahkshi remembered it all. And with the memory came something else, something none of its kind had ever felt before…

Fear.