Vinyl, Octavia, Twilight and Spike were in the tower. Vinyl came over with a book that read Ancient Siege Weapons. Vinyl shouted “Why don’t we make one of these, they sound like fun. They cause explosions.”

Twilight trotted over to Vinyl and opened the book, she opened and after quick skim she nodded “That does sound like fun, I could come with a plan.”

Spike ran over and smiled “Maybe if we put it on tracks it could move? We could even build a safety cabin for ourselves that could double as a control system.”

Twilight grinned “Let’s go and purchase the supplies. I have been saving up my stripend for a big project and this could be it.”

Octavia joined them “Are you sure this is a good idea?”

Vinyl nudged Octavia “Relax it’s going to be fun.” Octavia sighed as Twilight and Vinyl put on their saddlebags while Spike put on his backpack. Octavia followed suit and the four of them left the tower. Vinyl was grinning the hole way, Spike and Twilight were giggling to each other. Octavia looked at the three of them with concern.

Twilight smiled passing a bag of bits to Octavia and Vinyl “You get the gunpowder. We’ll collect everything else.”

Vinyl grinned galloping off, Octavia following in close pursuit. Spike and Twilight found their way to a shop that read Metallic Mechanisation’s Workshop. Spike entered first Twilight behind him, a massive stallion with a silvery coat and a short greying mane was behind the counter. Electronic and mechanical parts were everywhere. Twilight trotted over and put a large bag of bits on the table “We need 50 tons of steel, 200-300 high end computer chips and 40 metres of track treads as well as a high end track.”

The stallion frowned “This sounds like a big project for one so young.”

Spike frowned “We wanted to do a big project and we need a lot of materials.”

The stallion chuckled “I was just like that when I was young, name’s Iron Plate. Do you want it now?”

Spike nodded “We do.” Spike wondered how the others were doing.

Vinyl and Octavia where in a firecrackers store, Vinyl grinned placing the bit bag on the table “We want 500 tons worth of gunpowder.”

The owner was a red mare with an orange mane, she shook her head “Why should I sell you three anything. You are way to young to handle raw gunpowder.”

Vinyl complained “But...”

The owner shook her head “I am Flash Fire, I don’t just don’t provide...”

Octavia rolled her eyes before staring at the mare, her eyes glowing a pale grey. Flash Fire’s eyes glowed the same colour “You will provide us with 500 tons of gunpowder and then take our bits, you will tell no-one we were ever here.”

Flash Fire nodded wordlessly, as she did head to the back Vinyl looked at Octavia “You are quite scary, you know that right?”

Octavia rolled her eyes “I am a pony that eats liver, I’m supposed to be scary by definition.” Flash Fire dumped a huge bag of gunpowder and took the bits. The two fillies left the building and met up with the others at the castle gates.

Spike frowned “So where do we go to put all of this together?”

Vinyl smiled “To our secret hideout, it would be the perfect place to build it.”

Twilight raised an eyebrow “What secret hideout?” After they showed Twilight the hideout “This place isn’t big enough for our purposes.”

Spike grinned “Well then let me expand our hideout.” Spike focused growing three times his normal height and began digging through the dirt. The other three exited the hideout why he worked, an hour later they Spike walked up and let them in. They entered only to see of a huge chasm 500 metres deep and 500 metres wide, a huge staircase made of dirt leading down to the bottom.

Octavia raised an eyebrow as they headed down “Isn’t this overkill, it’s massive.”

Spike shook his head “We can do bigger things in here later. We can do all kind of science experiments, engineering and other projects down here.”

Twilight’s eyes widened as her mind raced through the possibilities. They reached the bottom and started building. Spike started using his fire breath and claws to mould the steel into shapes he wanted. Twilight and Vinyl started assembling shells. Octavia put together the treads and tracks forming the base. Spike attached the base central chassis and Twilight got to work putting the mechanisms together. Finally the attached the 200mm cannon onto the top of the central chassis.

The four of them looked at the assembled vehicle in front of them, Twilight beckoned to them “Time to test out her functionality.”

Spike nodded as Vinyl grinned “Let’s fire this baby up!”

Octavia sighed “Let’s not make a mess.”

The four of them jumped entered the top of the cabin, Twilight took the driver’s seat. Vinyl took the seat next to her, Octavia took the Navigator’s chair while Spike was in the Cannoneer’s seat. Twilight sounded off “Octavia use the sight scope to map out our movement and relay me information. Vinyl activate command prompts 1,5 and 9. They labelled with those designations. Spike, ready the cannon for firing.

Twilight grinned as the others attended to their duties “Prototank Mark I, ready for to go.” Twilight pulled the ignition. The Prototank accelerated quite quickly for a vehicle of it’s weight.

Octavia frowned “Aren’t you going to fast!”

Twilight giggled as she turned the Prototank with ease “Give me more credit, I know what I’m doing.” She then turned to Spike “Fire the cannon.”

Spike grinned as he fired upward the huge explosion shaking the entire area, Octavia gulped “Um are you sure building this thing was a good idea. We could destroy Canterlot with this thing if we tried.”

Vinyl laughed “Relax, we aren’t going to do that. This place is perfect for testing such explosive, relax will you.”

Spike frowned “We should reinforce this place, if we continue the whole place could collapse on our heads.”

Twilight nodded “That’s fair but once we do that we can really start building this place up.”

Over the next week they were able to use the materials they gained from Spike digging the huge base and used the bits they acquired to reinforce the whole area. They were even able to create separate areas for different task types.

Author's Note

Sorry this chapter took so long. I had a few idea for this chapter and didn't like them, then rewrote it again until I was satisfied. I hope this is good.