2:08pm Trolberg Library, Trolberg, 15 days after the anomaly
"There. I think that's everything." Tails stared proudly at his schematics.
"Let's have a look?" Frida peered at the schematics for herself, as Hilda tried to join in.
"Goodness me. How do you even read any of this?" Hilda asked, dumbfounded.
"Practice." Tails replied. "I do this a lot."
"I can see that. This level of mathematics is more advanced than even I know." Frida replied. "You checked all of it?"
"I've checked them at least three times. The numbers are correct. Now all we need is materials." Tails rolled up the schematics and tied them up in a rubber band for safe keeping. "We'll need some scrap metal, copper for wires, and you know, somewhere safe to put it, where people aren't just going to randomly walk into it."
"Like atop the wall, maybe?" Frida suggested.
"That could work." Tails replied.
"There should be plenty of recycling places where we could get some materials." David added. "Though I do wonder how we'll move the stuff once we get it."
"We won't need too much. If anyone has any wheelbarrows to spare, that would be ideal." Tails replied.
"Got it." David replied. "Let's see if we can borrow one. Are you coming with me?"
"Just a second, I'll be right there." Tails tidied away his schematics and joined David as they searched for materials.
"Let Sonic know where I've gone when he comes back, okay?" Tails reminded the others.
"Will do." Frida replied, as she continued her magic revision.
Having managed to borrow a wheelbarrow from the Sparrow Scout Hall, David and Tails headed to the first place that David had thought of. The recycling centre in question looked a lot cleaner and emptier than normal, David noticed, as they walked to the foreman's office.
Tails knocked on the door and waited for the foreman to open it. The man stared at Tails, incredulous that someone like him would even exist in this world, and, after rubbing his eyes, he worked up the gumption to speak.
"Evening. What do you guys want?" he asked gruffly.
"Uh, we were wondering if you had any scrap metal to spare. We're working on a small project, you see, and..." Tails began.
"Not sure I can help you, I'm afraid. Some bald fellow with a bushy moustache came up to me asking for the same thing. Dunno what he's using it for, but he's clearing the entire skip on a daily basis, so there might not be anything there to find." the man apologised.
"Huh. Figures." Tails tried his best to stay calm. "Do you mind if take a look anyway?"
"You can look, but don't go digging anything out without a hard hat and vest. If you need my help, come and ask."
"We will, thanks!" Tails grabbed a hi-vis jacket and hard hat and made his way to the scrap metal skip. As luck would have it, there were about twelve decently sized squares of sheet metal laying in what was an otherwise empty skip.
"Find anything?" David asked as he caught up to the fox.
"Yep! Exactly the sort of thing I was looking for." Tails replied.
"Want me to help carry that?" David asked.
"Sure, but get some gloves, this stuff has sharp edges." Tails instructed. After David had fetched some from the foreman, the pair took the sheets of metal and loaded them into the wheelbarrow. Once they'd done that, they thanked the foreman, returned the gear they'd borrowed, and wheeled the metal back into town.
"Where are we going to put this? Tails asked. "I know Frida suggested we build the portal up on the wall, but surely we'd need some kind of approval for that, right?
"Mum offered to let us use her section of the wall. She volunteers for the safety patrol when she has time." David clarified.
"Oh, good. I need to start building this as soon as possible. Can you get the schematics for me so I can get to work?" Tails asked, as they stopped in front of the library.
"Got it." David gave a small thumbs up as he walked in, heading into the basement where Hilda and Frida were still studying. Sonic had evidently returned, and was waiting impatiently for Tails to come back.
"We're back." David announced as everyone else turned to look at him.
"Is Tails not with you?" Sonic asked, leaning against a bookshelf with his arms crossed.
"He's waiting outside with the scrap metal; he seems to be in a hurry to start building." David replied. "Where are the schematics again?"
"Right here." Hilda reached over the table and grabbed them, handing them to David.
"We'll come and join you on top of the wall in a minute." Frida told him.
"Okay, see you soon." David replied, leaving with the rolled-up schematics in hand. Leaving the library, he handed them to Tails before heading towards the wall. Wheeling the barrow up a series of stairs, Tails and David laid everything down at the top and waited for the others to catch up.
"Remind us again why we're up here?" Frida queried.
"Eggman is up to something." Tails began.
"What else is new?" Sonic chimed sarcastically.
"Let me finish." Tails pleaded. "When David and I went to the recycling plant, the foreman there mentioned that someone with a moustache like his was clearing out the skip on a daily basis. Given that we have enough metal here to build a portal ourselves, I can only imagine he's using it to build something much larger, like an army of robots. I know that doesn't sound too difficult to defeat but I think Eggman wants to take the advantage of using it when were not around." he hypothesised.
"You mean he might attack Trolberg after you've gone?" Hilda asked.
"Possibly. But more likely he'll try to take over our world first while its defences are depleted. From there he could accrue a lot more resources and take over more worlds, if we don't stop him. Which means we need to get started pretty quickly, because he's already several days ahead of us.
"Got it, I guess I should keep looking for him, while he's still here." Sonic replied, dashing off through the hills and into the distance.
4:15 pm, Van Gale's Laboratory MkIII, the same day
"Victoria, could you pass me that torque wrench?" Eggman held his hand out as he slotted in the final bolt.
"Here." Van Gale handed him the wrench, as he tightened the bolt up.
"Right, that the portal completed. How many Necrobots are we up to now?"
"838, once I finish conjuring up this one." Van Gale replied.
"Marvellous!" Eggman replied. "That should be enough to get us back to my lab."
"Isn't this a little bit overkill?" Van Gale opined, staring at the uniformly array of robots standing in line, waiting for orders. Eggman had based their design off of his very own Egg Pawns, although since they were made of unpainted scrap, the Necrobots looked a lot cruder, though no less intimidating.
"Oh, there's no such thing as overkill when it comes to Sonic." Eggman chortled.
"I guess." Van Gale couldn't find any reason to disagree with that. "Do you have any plans beyond returning home to your lab and rebuilding?"
"Of course. I always have plans. For years I've dreamed of building a theme park styled after yours truly." He explained, gesturing at himself. "Not surprisingly, any time I've tried to realise that dream Sonic and his buddies always destroy my handiwork."
"Oh, how horrible." Victoria sympathised strongly with his plight, given Hilda's habit of destroying whatever Van Gale had built.
"I know. What sort of monster would destroy a theme park?" Eggman asked rhetorically.
"Perhaps this time, we can both get a fresh start." Van Gale muttered miserably to herself.
"You want to follow me through to my world?" Eggman acted surprised.
"Naturally. For decades I tried to solve problems for the sake of humanity. I altered weather patterns, I tried to strike a balance between us and the natural world, but the world didn't want me, and now look where I am. Down here I am isolated, save only for my creations, a pariah to the only civilisation I've ever known, and, as you know, this place has precious little when it comes to power and resources. This world will consume itself of both of those things soon enough, and I don't see myself being able to stop that. So will you let me into your world, if only for a little while?"
"You needn't have gone into so much detail. I'd have said yes regardless. Eggman smiled. "I need an assistant with me that I can trust. My last protégé turned on me the first opportunity that he got.
"You can count on me." Van Gale smiled proudly, filled with anticipation at what lay on the other side.
"Right then. Let's give these boys their marching orders." Eggman slotted the Warp Topaz into the receptacle, and powered on the machine, putting his plan into action. "Onward!" the robots began to march towards the portal, whilst Eggman and Van Gale hopped into their Eggmobiles and followed the first of them through.