hat do you mean, we're the killers?" asked Gregor.

"You know how things have two names. Rats are gnawers. Bats are fliers. Most people call Temp a crawler, but my mother called him a cockroach like you do," said Hazard. "And she said 'spider' like Boots."

"When Sandwich came down, he used 'spider' as well," said Howard. "But in time, 'spinner' became the more popular term."

"In the Underland, creatures are named for what they do," said Hazard. "That's why they're the stingers," said Hazard, nodding to a scorpion. "And Ares is a flier. And we're killers."

"I've never heard that before," said Gregor.

"We do not like the name, so our friends do not call us by it. And our enemies do not use it to our faces, either, because it makes the humans seem too strong," said Howard.

"Killers, huh?" Gregor said to Luxa. He had seen too much in the Underland to give the humans some sort of "good guy" status. They were capable of doing plenty of damage. But what had they done to have earned the name "killers"? Had they really killed more than any of the other creatures?

"It is a very old name. As Howard says, we do not like it," she said. "I am surprised to hear you use it, Hazard."

"My father used it sometimes," said Hazard.

"Well, your father was not... he was not really one of us anymore," said Luxa. "I mean, he did not want to live with us."

"No. He did not like being a killer," said Hazard.

"Stop it! Stop saying that!" said Luxa.

Hazard looked at her in surprise. She almost never rebuked him. "Why? It is true. Humans are known for their killing."

"It is a very old name, Hazard," said Howard. "One we would like to see fade away entirely."

"I don't know how that will happen," said Hazard earnestly. "It's what most creatures call you in their own tongues, even if they do not use it in English. The hissers, the spinners, the crawlers, almost everyone."

"Well, that is an interesting piece of news," said Luxa, shooting a look at Temp.

"An old word, it be, old," said Temp uncomfortably.

"How could you not know that?" asked Hazard.

"Because you and your dad were the first humans who ever learned to speak another creature's language," said Gregor. "Better let it drop now, Hazard."

"I'm sorry," Hazard said, squeezing Luxa's hand.

"It is of no account," she said, giving him a hug. But Gregor could tell she was still unhappy about the whole conversation.

It was not exactly lifting Gregor's spirits, either. If the humans were known as killers, then what did that make him? Their warrior? Their rager? A killer among killers? For the first time he began to wonder what this war Luxa had declared would personally mean for him. Was it assumed that, as the warrior, he would participate? He had never fought in a major war. He'd only been in a couple battles and never faced off with an army of rats. He was, in reality, very inexperienced, but he doubted that would matter. What did the Underlanders expect of him? Did he have a special role? Like possibly... killing the Bane? Gregor pushed the idea from his brain. No point thinking about that until he was back in Regalia with Vikus to talk him through "The Prophecy of Time." And then what? Then he would have to decide whether he was in or out.

It had been a long day. Starting with that breakfast of slimy shellfish, then the flight up Hades Hall, the Bane's speech, the rat attack, and the scorpions. Somewhere in that mess was the lovely peaceful time he had shared with Luxa, when they'd leaned back-to-back in silence. He wanted to pull the experience out and examine it and relive it. But the minute he'd curled up beside Boots, he fell fast asleep.

In the morning, the scorpions helped them work out their next move. The rats would have the mouth of the tunnel blocked, just in case any of them survived. But the scorpions knew the area far better than the rats. The best idea seemed to be to follow a series of tunnels deeper into the Firelands. Although it would mean a longer flight back to Regalia, they should have larger open spaces to fly in and less of a chance of being trapped by the rats. Luxa did not bring up her plan to pursue the mice, but Gregor knew she still meant to find them.

"And they say be watchful of the currents," said Hazard.

No one was too worried about the currents, though. Gregor had ridden the airstreams up and down to the Underland dozens of times now. He actually kind of liked the currents.

As they were saying their good-byes, Luxa had Hazard translate a message for them. "Tell them from this day on, the humans consider the stingers their allies. Tell them we wish for nothing but peaceful relations between us. Tell them when they let Thalia live, they entered our hearts."

Hazard relayed the message. The scorpions came back with a similar, if less emotional, pledge. But then, since they'd had very little experience with the scorpions and there were several different languages to take into account, no one could really judge its tone. You had a scorpion speaking in Crawler to a seven-year-old boy who had only recently learned Crawler and spoke a mixture of Overland and Underland English. Things could have been lost in translation.

Gregor just considered it a huge victory that everyone got out of the situation alive. And there did seem to be the beginning of trust. Boots's affection for the babies had made a good impression. The scorpions were trying to help them evade the rats.

"You know who'd have loved that? Your grandpa," Gregor told Luxa as they started down a tunnel on Aurora's back.

"Yes, Vikus is very fond of peaceful resolutions. So am I. I just believe that in his eagerness to achieve them, my grandfather can trust too soon. Remember when we visited the spinners? We ended up as their prisoners," said Luxa.

"But they didn't kill us," said Gregor.

"They almost killed me!" said Luxa.

"Well, you were trying to escape," said Gregor.

"And then it took Gorger and his army slaughtering the spinners for them to ally themselves with us," said Luxa.

"They might not have ever done that, though, if they didn't trust Vikus," said Gregor.

"Perhaps not," said Luxa.

"I'm just saying, it's nice when nobody gets killed," said Gregor.

"That is pretty talk for a warrior," said Luxa. "Not the sort of thing you will want to be shouting out before a battle." She mimicked his accent. " 'Remember, it's nice when nobody gets killed!'"

Gregor laughed. "Who knows? Maybe that's exactly what I should be shouting before a battle."

He was in a strangely good mood given the circumstances. He was far from home, surrounded by enemies, many of his companions were wounded, his family was worried sick, the mice were being driven who knew where, the Bane had turned into some sort of evil genius leader, and there was some ominous prophecy lying in wait for him. And here he was joking around with Luxa. Maybe it was just the relief of still being alive. Or maybe it was something else....

Luxa was leaning against his backpack again, her head on his shoulder. Howard flew by and gave Gregor a disapproving look. What? He hadn't made the seating arrangements. Howard had. It was more comfortable riding with someone to lean on. Probably Gregor was in for another speech about dates and queens and things. About how nothing was right about him liking Luxa.

"Oh, who cares? My mom will probably send me home the second we reach Regalia, anyway," thought Gregor. But the idea didn't make him feel happy. The walls and floor of the tunnel began to transform from a dull gray to a shiny black. Light from Gregor's flashlight and Boots's scepter danced off the surfaces and reflected to other spots. When they landed at a spring-fed pool for a break, Gregor stooped down and ran his fingers over the surface beneath his feet. It was smooth. Almost slick.

Luxa examined the ground beside him. "It is like black glass."

"I think it might be obsidian," said Gregor.

Boots quickly discovered the slipperiness of the floor. "Look, Gre-go, I ice-skate!" she said, sliding wildly over the black surface, waving her scepter.

"I want to try, too!" said Hazard.

Howard grabbed Hazard before he could work up much speed. "Oh, no, you do not, Hazard. The last thing you need is another head injury."

Luxa was still focused on the floor. "What is obsidian?" she asked Gregor.

"It's a kind of rock you only find around volcanoes. It's made from cooled lava," said Gregor.

"You must be right. The Firelands are known for their volcanoes," said Luxa.

"Active volcanoes?" asked Gregor. "Do they still work?"

"Why would they not?" asked Luxa. "They cannot break."

"They can become dormant. Asleep," said Gregor.

"I do not know, then. No human has ever stayed long enough to study them. The air is too bad for extended visits," said Luxa.

Suddenly all four of the bats lifted their chins, usually a sign they had sensed something alarming.

"What is it, Aurora?" asked Luxa.

"I do not know. Some creature moves within," said the bat, nodding in the direction Boots was heading.

"I cannot detect its shape," said Ares, in a puzzled tone.

"Come back, Boots!" called Gregor. But either she wasn't listening or she was ignoring him. "Hey, I'm not kidding!" he said, taking off after her. After about ten steps, he lost his footing and landed on his rear end. "Boots!"

"Wheee!" said Boots as she spun across the floor, and then suddenly she gave an "Uh-oh!" and dropped out of sight.

"Where is she?" exclaimed Hazard.

"Ow!" said the little voice from the dark. "We bumped." Her sandals pattered around. "I know you!" she said. "Oh, ow...." But this second "ow" was a sound not of pain but of sympathy.

Gregor ran toward her voice and would have fallen as well had Howard not caught him by the arm and lifted him back. They were at the edge of a large pit that was about twenty feet deep. The obsidian walls were very steep and smooth.

"Gre-go! Gre-go!" Boots was trying to climb out of the pit, but she slid back down its side almost immediately. "Gre-go, see who is here! Ow!" She pressed her hand against her teeth and then pointed her scepter at the creature beside-her.

A scrawny rat lay a few feet to her right, panting for air. His front teeth were way overgrown, at least by a foot, and had locked together, spreading his mouth in a horrible grimace and distorting his face painfully.

But Gregor could still make out the scar on the agonized face. "Ripred," he said.

The rat locked eyes with him but was unable to speak.

"Don't move," said Gregor. "We're coming."