“Mouse-Breeder’s mice,” said Umbo. “They have human genes in them. Including the genes of time manipulation. Only in these mice, the genes are expressed by time-displacement of inanimate objects. They can put anything anywhere.”
“So when they put a cylinder in my throat—”
“It’s what some Odinfolder humans told them to do,” said Umbo. “And they obeyed, because they knew that we could retrieve you.”
“Though it was harder than they thought,” said Rigg. “Because we didn’t want to retrieve you from a point before you learned all that you could learn here.”
“Whatever it is you learned,” said Olivenko. Was there a bit of scorn in his voice?
“We’ve spent nearly a year here, all told—a whole year since we left Ramfold and went to Vadeshfold. Which of the things that happened in that time should be erased?” asked Loaf. “We wanted to save your life, of course, but we didn’t want to kill a year of it in the process.”
Param felt uneasy, thinking of a version of the future in which her burnt-up body had no head left on it. “What will we do now?”
“Go to the border with Larfold,” said Rigg. “The wallfold to the north. Where Father Knosso was murdered.”
“We’re going to go back earlier and save him?” asked Param.
“We don’t dare,” said Umbo. “Not yet, anyway. We can’t go back before the time when Rigg took control of the Wall.”
“The flyer won’t pass through the Wall,” said Umbo. “We have to walk through. I’d rather not do it while experiencing the agony of the Wall.”
“We’ll go through the Wall at almost exactly the time Rigg took control,” said Loaf. “While we were still hiking around in Vadeshfold. Before we ever appeared here.”
“But they’ll see us,” said Param.
“Who?” asked Rigg.
“The Odinfolders.”
“Oh, well—they probably will,” said Rigg, “since they seem to cluster around the Wall. But they won’t know to stop us.”
“Unless the mice send them another Future Book,” said Umbo, laughing.
“Is that who’s been writing the Books of the Future?” asked Param.
“No, no,” said Olivenko. “This is the only timestream in which these mice existed. All the other Future Books were sent using the original crude displacement machine, before time-shifting was turned over to the mice and became precise.”
“And did the Odinfolders—the mice, I suppose—really alter Father’s genes? And create Umbo outright?”
“Yes,” said Rigg. “But this is the first timestream in which we existed. Ramex was carefully breeding for time-shifting power, but he hadn’t reached us yet, not until the mice intervened. And he would never have reached our level in his breeding program, because Garden would have been destroyed first.”
They explained to Param all that they had learned in the starship. And Param could see that something else had happened, too—Umbo and Rigg were still a little wary around each other, but Umbo was actually cooperating with Rigg and not arguing with every little thing he said. Something happened on that starship, and Param asked what it was.
“I died a couple of times,” said Umbo.
“Really?”
“Copies of me,” said Umbo. He explained how that worked, and Param nodded. “The way there must have been two versions of me back in the library, when we were running away a minute ago. Six months ago.”
“Only because your earlier self didn’t see your later self, and so you didn’t turn away from the path in which you time-shifted, you didn’t cause yourself to split,” said Olivenko.
“But I still died,” said Param.
“Only it’s all right,” said Umbo, “because we don’t remember dying.”
“It’s not all right,” said Rigg.
Param and Umbo both looked at him, waiting for an explanation, and Param was surprised to see how upset Rigg looked.