CHAPTER 9 — DISCOVERY

Mina lost a Firefly on a Tuesday, and that was how they learned the size of the thing.

She had been pushing them farther each night, past the wilted garden, past the edge of anywhere she had ever scanned, mapping the dark the way she mapped everything, by walking up to it until it told her something. On Tuesday the farthest one, the one she called Nine because she was not sentimental about names the way Kai was, went quiet.

It did not crash. She knew her crashes. This was different. Nine sent back four seconds of readings that made no sense, a cold so deep her scale had no bottom for it, and then it stopped, not the stutter of a broken machine but the clean nothing of a machine switched off from the outside.

She brought the four seconds to the others the next morning, put them on the laptop, and let the numbers talk, because she did not have words big enough and did not trust the ones she had.

ARC-7 looked at the four seconds for what, in a being that read a world in an instant, was a very long time.

"The first dark," it said finally. "The one that broke your home. It was a scout. One probe. A finger." It did not look up from the readings. "This is the hand."

It built them a picture out of Nine's last seconds, cold cyan lines in the morning air, the way it had built the arena. The clearing, small. The wilted garden, a little bigger. And then, out past both, where Nine had died, a darkness with no edge they could find. A mass of the un-light, gathered and waiting, so vast that the thing that had taken everything from Zaro did not register at the same scale.

Kai said a word his mother would not have liked.

"You should know what you are choosing to fight," ARC-7 said. "I would have waited until you were stronger. You are not going to be stronger before it comes. So."

It told them the way it told everything, plainly, without softening. But Zaro had learned to hear the thing under the plainness, and the thing under this was old, and tired, and standing very close to grief.

The dark did not want their clearing. The dark did not want anything, the way they meant the word. It served. Far out, past the frames ARC-7 was built to watch, there was an absence. Not a thing. The opposite of a thing. A place where light went and did not come back, that had been growing longer than ARC-7's people had been counting, hungry the way a hole is hungry, by being empty and pulling everything toward the empty.

The Ink was its hand. Its scout. It went ahead into the small worlds and tested them and learned how they broke and mapped them, and when a world was ready, the hunt came, and the world went out like the others, and the absence grew by exactly that much.

"A black hole," Mina said. Quiet. The science of it arriving in her like a cold stone.

"That is your word for the smallest and simplest version of the idea," ARC-7 said. "What I am describing is not small. It is not simple. And it is not finished growing."

"I have watched it happen," it went on, "more times than your number system holds. It is what my class does. We watch worlds end and we file them. We do not cross." The cold light dimmed. "I have watched a great many lights go out, and filed each one in its place, and it never once fit a column that I might have done otherwise. There was no otherwise. There was only the watching."

It looked at Zaro.

"Then your world's dark went into a small house, and a small spent thing carved a mark into a dying tree and refused to go out. I had no column for it. In every world I have watched end, not one of them refused." A pause. "You are the only anomaly I have ever recorded. I crossed for an anomaly. I did not know it would also be a war."

For a while no one said anything.

"So we can't win," Kai said. Not giving up. Just saying the true thing, the way Mina had taught him to. "Even if we beat this one. There's more. There's always more. It's the whole sky."

"Yes," ARC-7 said.

"And we can't save it. Any of it. Really."

"No," ARC-7 said. "Not the way you mean save."

Mina had gone very still, the stillness of a mind running a number it did not want the answer to. "One clearing," she said. "Against that. We hold one clearing, and the rest of everything still goes out eventually, no matter what we do here."

"Eventually," ARC-7 agreed. "Yes."

Zaro had been quiet, looking at the cold map, at the edgeless dark past the wilted garden, at the place where Nine had been switched off. He was brighter than a week ago. A little. Not enough. He would not be enough in time, and he knew it.

He thought about the moth.

The moth on his first night, dropping powdery and slow onto the windowsill, and his hand cupping around it in the dark. One moth, against all the dark there was. He had not been able to save the dark in the world. He had cupped his hand around one small living thing and said you're okay, and that had been worth doing, and the size of the dark had not made it not worth doing.

"I'm not trying to save everything," he said.

They looked at him. His voice was small, and it did not shake.

"I couldn't even save the clover," he said. "I know what I can't do. I learned that one pretty well." He looked at the black tree, the gold line still lit in it. "But the deer's clover mattered. It mattered even though I couldn't keep it. The cabin mattered. Boop matters. The shelf mattered. The thing we do in the arena, where we keep the seed lit, that matters. And none of it stops mattering because there's a big dark somewhere that might outlast us. That is not how mattering works."

He had never said so many words at once. He was surprised to find he meant all of them.

"I can't defend the sky," he said. "So I'm going to defend ZaroLand. I'm going to defend us. That's the thing I'm able to do, so that's the thing I'm doing."

The clearing was quiet.

"Okay, that was kind of incredible," Kai said, a little wrecked. "For the record. You shouldn't be allowed to just say things like that."

"I'm in," Mina said. She had not stopped doing the math. She had only decided the math was not the only true thing in the room. "Eyes open. Knowing it's one node. I'm in for the node."

ARC-7 was looking at Zaro with the regard that Zaro had stopped finding cold.

"I crossed for this," it said, almost to itself, as though confirming a reading it had run many times and not believed until now. "I did not have the word for it before. The word is this."

Something moved in the rafters of the ruined cabin. A small gray weight, settling in, warily, keeping one bright eye on ARC-7 from a safe height. Boop had come back. Not all the way. But back, to the warm broken place that was theirs, because it was theirs.

Zaro looked up at it and felt his light come up a shade on its own, no sun required.

"Hey," he said. "You came back."

Boop, with great dignity, pretended it had never left.

They spent the time they had left getting ready, which was not much time, because the hand was coming and ARC-7 could measure how fast.

The plan was the arena plan, scaled to the size of the fear. Mina's Fireflies would see the dark coming and call it. ARC-7 would hold what it could hold. Kai would mark the dark and move it. And Zaro, who could not yet be the bright thing that held a dome, would do the job that turned out to be the hardest and the simplest, the one Mina had named for him in the sim and that had been the real job all along.

Stay lit.

On the last evening before it came, they sat in ZaroLand and did not train, because Mina said they should rest, and Mina was usually right. Kai lay in the dead grass and named the stars wrong on purpose so Zaro would correct him, except Zaro did not know the real names either, so they made up their own, which was better. ARC-7 stood a little apart, watching the tree line the way it would always watch the tree line. But it stood closer than it used to.

The gold line in the black tree held its light. Above them the torn door in the sky waited, and out past the wilted garden the edgeless dark gathered itself to come and put this small world out like all the others.

Zaro was not bright enough. He knew it. They all knew it, and none of them said it, and none of them left.

"Okay," he said. To the dark, to the tree, to the four of them and the squirrel. The word he had instead of all the others. For once it did not mean I am barely holding on. It meant something nearer to come on, then.

"Okay."