Rigg led them along Umbo’s path. It followed the obvious course—through the increasingly finished-looking tunnel toward the ship. It was only when they reached the beginning of the bridge across the gap between the stone and the starship that Rigg saw something that he couldn’t explain.
“Umbo shifted time here,” he said. “On the bridge.” Rigg stepped out onto the bridge, walking Umbo’s route. “He turned toward the edge, and then suddenly jumped back and stepped here. Then he jumped back again and stepped there. But the paths also fork, as if—but they’re a little different, not quite Umbo, not—”
“See what you can figure out without jumping back to look,” said Loaf.
“You think the expendable was trying something?” asked Olivenko.
“I know he was,” said Loaf. He walked to the edge of the bridge and pointed downward.
Umbo’s dead body lay crumpled on the stone below the ship. Even though Rigg had seen Umbo’s path go on inside the starship, it still made him gasp, still stabbed him with grief.
Not far off, but only visible from the other side of the bridge, lay his dead body again.
“Silbom’s left eye,” whispered Rigg. “Two of him. Two copies. But he’s not dead, Loaf. The main path, the real path, it goes on inside the ship.”
“I’ve always wondered what happens when you or Umbo go back in time and warn yourselves,” said Loaf. “Changing your course of action. Does the old path persist?”
Rigg blushed, embarrassed. “I’ve never looked. I’ve never paid attention.”
“You made your original choice, you took that path, and the effects of it remain real,” said Loaf. “But when you warn yourself—”
Olivenko finished the thought. “Your path takes a different turning. That becomes the real path. But the old one—”
“This is different from a mere warning,” said Rigg. “Umbo didn’t appear to his earlier self, he actually jumped and physically moved himself in time. But that still bent the path of his previous self, because here—he appears in front of his slightly older self. Same thing with the second jump. So his previous self no longer takes the action he used to. Which is why there’s a new path. A slightly different path. Now the Umbo who time-shifted on the previous path doesn’t time-shift.”
“So he stays in existence,” said Loaf.
“He copies himself,” said Olivenko.
“You could make an army of yourself,” said Rigg.
“Didn’t work out so well for these two,” said Olivenko.
Just because one version of Umbo remained alive didn’t change the terror and pain these two Umbos must have felt. Almost by reflex, Rigg prepared to jump back in time, at least to understand the situation, if not to fix it.
“No,” Loaf said to him.
“But I have to—”
“Umbo’s alive,” said Loaf. “There’s nothing to fix here.”
Rigg understood at once. “If I suddenly appear, it might change more than I want to change.”
“We don’t know what Umbo has done. What we might undo by appearing here. Let’s talk to him, if we can, before we start taking action that might cause more harm than good.”
Rigg knew good advice when he heard it. Loaf might not have the ability to time-shift, but that didn’t stop him from having a clear understanding of how it worked, and when it might not be wise to use it. He and Umbo had had enough experience with failure in their attempts to get the jewel from the bank in Aressa Sessamo. Loaf had learned a lot about the unexpected, damaging changes you could make. And that was before Umbo learned how to physically transport more than an image of himself into the past.
“What if one of them isn’t dead?” asked Olivenko.
“They’re dead,” said Rigg.
“How can you be sure from up here?”
“Their paths don’t go off the bridge,” said Rigg. “They were dead before they fell.”
“Careless of the expendable,” said Loaf.
“If you kill a discarded copy of a time-shifter,” said Olivenko, “is it murder?”