Okay, this is a nice detail. Chopper wasn’t in the crew in Loguetown when sea stone was introduced, he wasn’t in Crocodile’s VIP cage during Alabasta, and was knocked out for the whole end of Skypiea when Wyper was blasting Enel (temporarily) to death. Of the people in the crew, he’s the only one who wouldn’t know what sea stone is.

This wasn’t the scariest thing that Fox had ever done. He wasn’t even sure when talking to his sister had become a scary event for him. Yet there he stood, frozen outside her bedroom door the day after Christmas, unable to bring himself to knock for her to let him in. He stared absently at the familiar decals and doodles covering the white paint of the door, his mind running 100 miles a minute, and he wondered if this was really such a good idea. What could he possibly say to his sister to make her understand how worried he was? ‘Hey Peach, just so you know, for the past six years I’ve been best friends with the son of Uncle Trevor’s political rival and now he’s in the hospital and I need you to drive me there in secret!’

"The tendril monster's main form of offense is to entangle its prey in its tendrils and to feed on their lifeforce, correct?"

"To oversimplifiy things," the merwoman said, "Yes."

"But because of my accident, long story, I'm filled with unstable quantum energy. So when the tendrils were feeding on me, they were really feeding on that. That's why I'm awake when most of the others are not."

"Your point?" the merwoman asked.

"My point is, you see, when the instability builds up to a certain degree I have to drain it."

"And when I drain the instability it has an effect on my body."

"What effect?"

"My body changes...into another body. So when we were in trouble and things looked bleak, I went on the assumption that it had absorbed enough of my instability. And I used my pocket stabilizer on the creature. Soon after the island collapsed, so I'm thinking now it must have worked."

"I'm sorry," Crag said. "What does whatever you just said have to do with the island collapsing?"

"The island was the tentacle monster," I tried to explain. "The island was just a disguise to trap us."

"It's true," the merwoman, whose name I really should have known by now, but she never introduced herself, said. "The Giant Leechvine is known for disguising itself with a lure like a tropical island to capture land animals to eat."

"That monster was the entire island?" Crag asked.

"Yes," I told him, "so when I used my stabilizer on the monster it changed. And when the monster changed, it must've changed into something smaller, meaning that there was nothing holding the island together."

"Leaving a lot of empty space," Tam said. "So the island collapsed."

"Yes," I said, happy that someone else got it. "The island collapsed."

"When the monster became a smaller creature, its disguise, all the island accountrements that it was using to hide itself, fell."

"Fell right on top of us," Tam added.

"Yes. Maybe it turned out that wasn't the best strategy. But, hey, here we are."

"So, that thing in there...?" Crag asked.

"Is the monster, Yes."

"The Giant Leechvine," the merwoman corrected.

"So the monster was an entire island and is now that person in there?"

"That's how I understand it, Crag."

"Ok," Tam said. "So now what are we going to do with it?"

to be continued next week

The crystal found their ways back, undoubtedly using threads in the aetheric sea to follow, and returned effortlessly, so when Wren did finally address Hydaelyn again, it was in a different space.

Thank you! Now go for ending B to start losing your will to live!

(It’s always a weirdly high honor to get messages that I encouraged other people to spend money.)

To answer the question: pacting with Noir is the Gestalt process, so what we see in the prologue is both Yonah and original!Nier undergoing the process. It’s suggested in the Grimoire (I believe, although I might be making this up!) that there’s a genetic factor involved in the process that determines how well it takes; Nier was the Perfect Gestalt, and thus takes to the process without difficulty (and with some new superpowers), while Yonah (perhaps due in part to her inherently fragile nature, let alone genetic variables) almost immediately undergoes relapse.