"Urgh," Robotnik said, "it feels like I've just travelled from a different planet, in another dimension". The human found himself back in one of his old hidden bases. It was one of the ones he had dotted around the planet that he used as a base of operations between world domination schemes. Next to him was the red Knuckles-esque robot.
The scientist looked around the room; he was in robotics lab, full of parts and tools needed to make any number of machines. Around him were half completed prototypes, conceptual blueprints, and an assortment of wires, electrical devices, and a half drunk cup of coffee that the scientist was sure was close to reaching sentience based on how much mould it had accrued.
"First things first then." the human said, before picking up a microphone "All hands report to the robotics laboratory. Full inventory to be completed. No exceptions."
Almost immediately robots began pouring into the room, almost all of them Egg Pawns or some variation thereof, with a few giant hammer wielding ones, and some flying ones. They were leftovers, mostly defunct and a bit outdated, but the Eggpawn's in particular were versatile all around robots that could be put to just about any task, and could be used to good effect making better robots.
The inventory also revealed that the base was well stocked in materials, most of which had been collected from the nearby Rail Canyon Zone, as well as some of the crashed vessels that used to comprise the Egg Fleet. The base also had a large supply of fuel, and a good stock of raw iron.
But it was not without issues. The base was one of the smallest, there was no real ability to craft any kind of vehicle bigger than an Eggpod, and while there were lots of tools, there were no specialised tools, only generic robot building equipment. If he was to be stuck here, Robotnik's robotic work would take a back to basics approach. Also, the location made the base quite humid, and due to the length of time it had been unused, it had a smell of stale air to it that wafted unpleasantly into Robotnik's mouth whenever he spoke.
"You need to build the bodies for the others," the robotic Knuckles reminded.
"Yes yes," Robotnik shrugged it off, "and that is my first task. But I need to know what I have here. Maybe we can use some of my existing machines and save time."
"Your machines are animal powered, therefore incompatible. We cannot enter another soul's body."
"Trust me, I know that," Robotnik said, remembering the incidents that led to him being stuck in the ocean floor, "but I've just been shunted to a random location. I need to know what I have to work with, where I am..."
"You're in your base under what you call 'Frog Forest'" the machine interrupted.
"... and what's actually needed."
"What we need," the machine answered coldly, "is four more machines like this one," it said referring to its own body "built the same, so it can be inhabited, and then a machine that can be used to rid this world of the Chaos Emeralds."
"Right, but you don't understand that that's not simple." Robotnik replied, "I need to know why the prototype you've inhabited works, I need a machine that can find the other Chaos Emerald realties, and we left the only one of those under the ocean, and I need a Chaos Emerald to power it to begin with, which means that at best we can only remove six of them."
"Then get on with it," the robot replied, "I will go back to the ocean, and get the machine."
"Do you even know where it was?"
"I will find it." The robot said, as it left.
"I'm glad he's gone." Robotnik said after he left. He couldn't stand having demands made of him like that. But he also couldn't deny how impressive the creatures were. He'd seen them in action, he'd reviewed the footage from his sunken airship, and the more he saw, the more it seemed that the legends were true. Robotnik smirked; an idea began to form in his head.
Robotnik looked into his old computers and, after much searching; he found the old prototype schematics for the Metal Knuckles. He gathered all his robots, and save for the few he had guarding Charmy, he set them all to work on assisting him build these prototypes. While he himself got on with another research project.
Mind control had always been something Robotnik had been capable of. It was, as far as he was concerned an easy technology, and part of what made him able to power machines with animals. By plugging an animal in directly, the brain could be used as a processor, and so long as you kept that mind loyally obedient, any machine could be piloted by just about any animal. You simply changed some of the base survival instincts, and altered the perceptions of the machines sensors to suit whatever the mind was used to. The animal inside would assume it was acting normally, why the machine it piloted did what was necessary of it. Sure, more complicated machines required smarter animals, but generally it was simple enough.
But this was what Robotnik had been working on. He had machines he could physically wire up, and he had developed weaponised versions, one that used hypnotic suggestion and acute targeted radiation, but both had issues. The mechanical one had to be wired in fully and the weaponised version took several hours to take control of a subjects mind.
Robotnik looked at both technologies and began to ponder. What if there was a way to make it so that the weaponised version was inside the robot body? He could make the technology small enough, and fit inside, meaning he could control the mind without ever needing a physical attachment.
The only question remained, was whether or not the Monsters of Chaos could respond the same way to the slow suggestion. Robotnik scratched his moustache, there was only one way to find out.