Nick ended up making several trips back and forth between home and the Bolthole. It was getting harder to find more of the new element without getting into the water. Once he had enough for the time being, he settled in back home and checked that he had enough resources to make the expensive mystery booster for Petra.

“All right, let's do this.” Nick started the build.

Petra complained about lack of resources, and Nick started feeding them in. He still wondered where Petra held all the stuff during construction, before the product started coming out. He realized that he probably would never know.

After feeding in over a dozen rods of different elements, though, Nick was starting to wonder how long this was going to take. He had taught Petra the meaning of “time to completion” and took a look.

104 hours, 17 minutes, 23 seconds

“The hell? That's like...” Nick squinted as he tried to do math. “Four days?” He knew from experience that Petra would just pause a print if she didn't have enough materials, so it wasn't as if Nick had to stay awake that long, but every time he slept, he'd be delaying completion. So it would be more like six days.

It actually took eight days.

Nick found that he couldn't do much without Petra. He couldn't carve stone, he couldn't even give new instructions to the guys. He just had to sit around and wait, and feed in a large fraction of his total supply of several resources. At least he had his phone, so he could look at his pictures, play his messages, and play a couple of games. He was getting really good at them.

“This had better be worth it,” he muttered probably a hundred times during that week.

Finally, the progress reached 100% . The result of all that time and resources turned out to be a very small brick, not too different from Petra, only made with right angles. It was coated in that stuff that felt like flexible stone.

Intrigued, Nick found it on Petra's network using her control tablet. It still had that gibberish label. He switched it on... and nothing happened.

“Huh.” He stared at the object, then at the display. A number showed up next to the name: 0%. Ugh, I bet it's hungry for something. It wasn't enough that it consumed a huge fraction of my resources, now it is going to demand even more for me to use it? I hope this thing is worth it.

If you spot this narrative on Amazon, know that it has been stolen. Report the violation.

The new device didn't have input ports or a printer head, at least not that looked like Petra's. It didn't have decorations or indicators on it either. There were no clues as to what it might be for. Nick stared at it for a while, then gave up for the moment. He had Petra back finally, so he gave new instructions to the guys for expansion, then went back to trying to figure out food chemicals.

The next day, Nick checked on the new device, and found that it read Charging: 1%. He had mixed feelings about that. On the one hand, it wasn't a dud, and it was actually doing something. On the other hand, if that was energy charge, the new device would be drawing a massive amount of power and would take months just to charge up.

Maybe I should make more solar panels. Nick had determined that he didn't want to use power cylinders to provide energy because they dumped heat out the cold side, and that situation was already bad enough that Nick was gladly paying energy to make it go the other way. The other three energy generating systems still seemed to be either too big and expensive, or required more elements or whatever resources than Nick had.

A small job Nick had been procrastinating was making doors. He had improvised a crude one for the tunnel exit, but he felt he needed a proper door if he was going to try growing apple trees. He was pretty sure that the “dirt” he used was going to stink horribly, and wanted to keep the smell away from the rest of the place. He'd made air purifiers, but there were limits to what they could do.

He occupied himself with seeing how thin he could make a metal door and still have it be rigid. Unfortunately, he pushed it too far and his aluminum door became aluminum foil. Nick fed it back into Petra and tried again.

He was still stuck on what to use for a seal around the edges. Petra could replicate the cotton of his T-shirt, but it took a while and he was pretty sure that the cost was higher than it needed to be because of some extraneous chemical or other, like the mercury. Cotton still would probably be his best bet.

He wasn't in any hurry to start, because he figured he would only get a limited number of tries. Best to have everything as ready as he could possibly make it. He hadn't figured out how to get Petra to grind up rocks into sand for him. He figured that would be the first step towards proper dirt.

The next day, Nick checked on the mystery device. It now read Charging: 23%. Encouraged, he kept an eye on it over the next couple of days. When it reached 98%, he settled down with a bowl of tomato soup and a game on his phone to wait out the rest. True to the spirit of Murphy, though, the percentage didn't change before he got tired of waiting and went to bed.

In the morning, the menu listing read Charging: 99%. Nick went on an inspection of the work the guys had done while he slept. Happy that he hadn't screwed up the instructions, Nick got himself a sugar breakfast, checked that his phone was recharged, and went back to his game for a while.

100%.

Nick saw the display just as it ticked over. Nothing happened at first. He waited, then took a deep breath, about to curse the thing, when the display went blank. Completely blank.

Oh, shit.

Quickly Nick picked up Petra herself and looked at the tiny display; it was also blank. Oh, no. No, no, no, no. Please, God, no. Don't let Petra be bricked. Please.

Then the display lit up, showing in great big letters:

INITIALIZING