Mang eventually emerged from within Zone 3 dragging a large sled with an unconscious boar loosely strapped to it. The boar was huge, brown with black spots, and had long curled tusks. In its neck was one of Mang’s darts. Caruso went to help her pull the sled but quickly realized she had it under control. The sled was propped up on two of her walls, a short wall across its front, a higher wall near its back. As a result, the sled would slide forwards with Mang walking alongside it, continuously replacing the walls. She guided the sled up the side of the building, opened a wall directly into a boar pen, then raised the back of the sled enough to tip the boar inside the pen. It was an unfailingly practical use of walling.

Mang saw Caruso and hobbled over, he expected her to brag about her new boar and pester him for new theories, but instead she just said ‘Mang will go do an experiment now, okay?’ and made to head inside without waiting for a reply.

‘Wait, Mang. I need your help.’

She slowly turned around with a sceptical look. ‘Really?’

‘Really.’

‘The brain needs to use its hands?’ Her face began to light up, like a dog around feeding time.

‘Yes. I need help understanding your sketches. Can you please help?’

‘Yes! Mang can help. Where should Mang go?’

‘Lets go to the desk.’

‘To the brain station!’ Mang grinned and rushed inside, where she waited eagerly for Caruso. ‘How does Mang teach you?’

Caruso pulled out a journal at random and pointed to an autopsy of a failed anima. It didn’t matter what the subjects had been, they all looked the same inside. ‘I don’t understand anything here. What should I be looking at?’

‘You should look at everything.’

‘Yes, but what is the most important thing?’

‘The spine! Always look at the spine first.’

Mang pointed at the illustration where two spines crossed each other and connected only in the middle. She had a look of disgust on her face.

‘Tell me what you see exactly,’ Caruso said. ‘Is this bad?’

‘Mang sees two spines. Two spines is very bad.’ She flipped a couple of pages, and pointed to a different experiment. This one looked a bit less chaotic. Mang traced her finger down from the skull along a single spine, but halfway down it branched into two like an open zip. ‘This one is better. A single spine up here, but then it branches into two. Mang doesn’t like it when they branch.’

‘What does Mang like?’

She looked around the desk and spotted the journal that contained the three successful anima experiments. The first one was the woman-horse anima. Caruso had looked at this experiment many times. In this one, the horse had been used as the anchor. The disturbing result was a horse with human skin, hands and feet instead of hooves. After merging, given the horse was the anchor, it maintained the intelligence and mentality of a horse. Mang pointed to the autopsy illustration and stared lovingly at it. Caruso could see there was just one single spine, no branching.

‘Does that look like a normal horse spine then?’

‘Yes. Except it’s thicker. The two spines become one.’

Caruso also noticed a lot of organs, he wasn’t sure which of them were supposed to be there. ‘Is that the right amount of organs?’ Caruso asked.

‘It’s perfect,’ Mang said. ‘Every anima has two sets of organs.’

‘Even perfect animas? The organs never merge?’

‘They never merge, Mang can prove it. Let Mang do an experiment, it will have two sets of organs.’ She looked hopefully at Caruso.

‘You can later. Why don't the organs merge?'

Mang shrugged. 'The new body is bigger, it needs both sets.'

Caruso accepted her explanation and turned to the second anima autopsy. This one was the successful merger of two prisoners. Other than being larger, the notes explained that the resulting anima looked and acted identically to it’s anchor. Again, the autopsies showed two sets of organs and one perfect unbranching spine. Mang slowly traced her finger down its spine, making a soft pleasureful moan. ‘Perfect…’ she said.

‘So only perfect animas have the single spine?’

‘Yes, in perfect animas, their spines fuse into one. The spine is very important.’

‘Why? What’s so important about the spine? Has it anything to do with why we feel that cold drip down our spines when we use our walling?'

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‘You should know, you’re the brain ha ha. When the brain tells the hands what to do, the message goes through the spine.’

‘But isn’t it just a bone?’

Mang looked offended. ‘Not just a bone! No!’ Mang stalked off through the wallway into the experiment room. Caruso wasn’t sure if she was returning or not, he had no idea what to expect with Mang. But she soon came back holding one of her more advanced journals. Caruso hadn’t bothered studying these, as they were too in-depth and specialised to be of any use.

This specific journal was filled only with spine renderings. One page was dedicated to multiple depictions of a boar’s spine, it was a normal unmerged boar, Caruso didn’t ask why she had studied it. Mang pointed to a cross section of its spine. It showed a circle of bone with something in its centre. Mang pointed to it.

‘Is that marrow?’ Caruso asked.

‘No, not marrow. It’s the spinal cord, it’s all nerves and fibres.’ She pointed to another picture and traced the spine up to the skull and pointed out how the spinal cord reached out of the spine to attach to the brain.

Next she found the sketches of the two-prisoner anima. There was another cross section of the spine. Instead of a single spinal cord through its centre, there were two clearly separate cords running down the middle of the same spine. Another sketch showed that both cords attached to the brain. The horse anima was the same—the spine housed two separate spinal cords, both attached to the brain.

It was interesting. But Caruso wasn’t sure how to use any of this information. He supposed he could go back through all the experiments and divide the unsuccessful animas into those with branched spines and those with two separate spines. That could possibly lead to some discoveries.

Another thought occurred to him. ‘Mang is there any difference between, say, an Urchin’s spine and that of a prisoner from Jamala?’

‘Yes.’

‘There is?’

Mang flipped to a later page in her spine journal. She showed him comparison pictures of spinal cross sections.

‘They look the same,’ Caruso said.’

‘No, not same. The Urchin has a wider spinal cord.’

After looking at several more examples Caruso could see that Mang was right. The Urchin’s spinal cord was clearly thicker.

‘Mang, could there be mycelium in the spinal cord?’

‘Yes, there could be.’

‘Really?’

‘It’s possible.’

‘But do you think there is? What’s your opinion?’

Mang looked uncomfortable, ‘Mang doesn’t have an opinion. Nerves and mycelium is all just fibres. It all looks the same. It's all the same to Mang.’

Caruso looked again at how the bundle of fibres reached into the brain. ‘But is there any other reason why an Urchin or a Forester should have a thicker spinal cord?’

‘Mang doesn’t know. Mang is just hands, not brain.’

‘Well, for a set of hands you’ve taught me a lot. Thanks Mang. Would you like to do an experiment?’

Mang nodded eagerly, ‘Yes yes! What experiment? What should Mang do?’

Even though he had learned a lot today about spines and anatomy, Caruso didn’t feel any closer to discovering how a successful anima was made, and had no idea how to get there. But instead of shrugging Mang off with another pointless experiment, he decided it would be more useful to test some of the boundaries and limitations of the animashroom. As there was now just two days before Ferris arrived and seven days left before the Godshroom departed, Caruso wanted something useful to report back to the Foresters.

He joined Mang in the experiment room. She could barely contain her excitement and rushed around the room preparing things while Caruso outlined his plan.

Mang always tested the subjects right next to each other. This was so she could immediately check the resulting anima after feeding the passenger. But Caruso wondered what would happen if the anchor and passenger were on opposite sides of the room. Would the animashroom still activate?

It did. The anima was unsuccessful but of course that was to be expected. Caruso had contemplated just using solely moths for today’s experiments. He planned to do a bunch of experiments, and using prisoners seemed wasteful—not to mention a lot harder to stomach. But there was always a chance humans reacted differently than animals, which would make all moth-to-moth research useless. Also, Mang reassured him that they can always get more prisoners. So for today, they ran their experiments using moths for the passenger and prisoners for the anchor.

After creating an anima from opposite sides of the room, they kept extending the distance, searching for the limit. It was found when Caruso fed a moth from the study room while Mang waited eagerly beside the anchor's cell. The moth didn't disappear when Caruso gave it the animashroom. But as soon as he brought it back into the experiment room the moth vanished and instantly merged with the anchor—much to Mang’s delight. They quickly discovered the subjects had to be in the same Zone for the animashroom to take effect—the study room extended into Zone 3.

Mang was giddy with all the experiments. She told Caruso not to stop and reminded him again that she can easily order more prisoners. Caruso obliged her.

Next, they tested the range within a Zone. The plan was to walk a shroommoth an hour away before feeding it and see if it would still merge back with the anchor. Mang insisted on going as she had more Zone 4 experience and also that, ‘The hands are made for hard work.’ She took a shroommoth and her other supplies and waddled her way across Zone 4.

Caruso paced up and down the experiment room, waiting. After about an hour he heard a series of thumps coming from the prisoner’s cell which ended in a long drawn out guttural groan. No longer than fifteen minutes later, Mang arrived, red faced, covered in sweat, completely out of breath, and looking ready to collapse. Caruso thought something was wrong but she ran straight past him, towards the prisoner’s cell to check her latest failed creation.

—

The following day, Mang had left to go hunting and Caruso was in the study room going back through the journals, preparing a report of all that he had learned.

The ominous pulsing of a bullroarer sounded from the forest close by.

Could that be Mang? Does Mang have a bullroarer? Caruso kicked himself for not knowing.

He rushed out behind his room and peered around the side into the Zone 4 forest that surrounded the little clearing. The bullroarer’s whine grew nearer.

Mang appeared running from the tree line, bullroarer spinning in one hand, walls shooting up defensively behind her. Not far into the clearing she lurched to a stop and fell flat on her face, as if her foot had been threaded in place. She immediately boxed herself in with four tall walls.

There was a moment of silence.

Before Caruso could think to do anything, a female Urchin with a wooden pole ran around to Mang’s blinkshadow and blinked inside Mang’s box, breaking the silence with a faint wet pop.

Caruso knew what that meant. The walls of her box dropped away.

All that remained of Mang was a bloody collection of limbs and organs and bones arranged in a neat little square on the ground.