The next three months were a blur as Marcus and the others hunted pirates and took breaks at Loguetown. Originally Marcus only planned to hunt pirates, but any time he showed up, Smoker would be there to collect the pirates and wanted to spar. So Marcus would give everyone a day off as he went to spar with Smoker.
Smoker for his part actually put in effort and followed the training list Marcus gave him. He didn't have a training harness, but he did have access to training weights, so he used those instead. Marcus also gave the man a few ideas on how to use his devil fruit powers in more creative ways. It was mostly in ways that he used after the time skip in the manga. As for theories like making people breathe carbon monoxide…
Marcus didn't bring those up since he wasn't sure how he could counter them if they ever became true enemies. Probably with haki, but Marcus didn't feel like taking that chance…
About a month before Marcus's tenth birthday he received a call from Frank who told him his ship was completed. Marcus and the others were already headed back to Loguetown with another group of pirates at the time, so Marcus just told him he would be there soon. When they arrived at Loguetown, Smoker was there to collect the pirates and asked, "I heard your ship is ready… When do you plan to leave?"
"In a few days after a quick shake down cruise."
Smoker glanced towards Zeff who just walked down the gangplank with Sanji and Gin as he asked, "And what about your crew?"
"Ace is gonna take over as captain… But I am gonna have them focus on physical training after I leave. None of the pirates have been a challenge to them lately." Marcus said as he looked towards the latest batch of captured pirates.
Smoker nodded slowly before he asked, "Wanna have another spar before you leave?"
"Sure." Marcus said before he started walking towards the marine base.
Their fight lasted over four hours since Smoker refused to give up until he collapsed from exhaustion. Once finished, Marcus said farewell and headed to check out his ship. At the dry dock he met Frank who eagerly showed him the completed ship as he asked, "What do you think?"
Marcus stood on a platform overlooking the ship and studied it for a few moments before he said, "It's perfect. Hopefully it will last me through the Grandline."
"I've never been, but I've read about the place so I reinforced both hulls and the mast."
Marcus nodded as he asked, "What are the dimensions?"
"Since you wanted it designed to be run by a single person, I made it smaller than a standard caravel. It's just under thirty feet in length with a fifteen foot beam width and the mast is just over thirty feet tall." Frank said with a smile before he waved towards the ship and added, "Let me give you a tour."
The ship itself was built a lot like a standard thirty foot catamaran with its two hull design. Both hulls were as narrow as possible and while most ships could carry a ton of cargo, Marcus's ship was designed only for speed. The two hulls were connected at the very front by a large beam. From that beam to the bridge was an area covered in a thick canvas stretched tight that acted as a deck.
The bridge itself was where the helm was mounted along with the drive train for the hydrofoil system. It wasn't large by any means and only had a few seats. But it could be completely sealed from the elements and also had a place where Marcus could string a hammock if needed.
Connected to the bridge were entryways to both hulls. The left hull acted as the galley and had some room for storage that could also be accessed through a cargo hatch on top of the hull. As for the right hull it was basically the same for storage except it was designed with a bedroom and bathroom.
Behind the bridge itself was a small deck with a boat that could be used when there was no dock. Marcus didn't really need it because he had geppo, but it would work if he needed to load in supplies. As for the mast, it was integrated into the bridge but didn't obstruct his view. After the main tour Frank showed Marcus the hydrofoils and propellers underneath the ship before his men launched it into the water.
Besides the ship itself, Frank prepared a couple extra sails, canvas patches, spare parts for the drive train and a handful of other things that were already stored away. Before Marcus jumped on the ship for the shake down cruise, Frank stopped him and handed him a thick booklet as he said, "Here are the blueprints for everything we made, in case you need to rebuild something or want to remake the ship."
Marcus happily took them as he said, "Thanks, Frank."
"Don't mention it and remember to call me and let me know how she handles on the Grandline."
Marcus joined before he jumped over to his ship and waved goodbye as he said, "Don't worry, I will."
Marcus didn't take the ship to the dock at first, but opened the sail up and headed out to sea until it was close to dinner time. Since they arrived in the early morning that gave Marcus almost six hours out on the water as he tested out the ship. Over the next few days he headed out before dawn and didn't return until dinner or later as he pushed the ship as much as he could. Once he was satisfied with it he transferred his belongings over to the ship and then bought supplies for his trip.
The night before he left his brothers and everyone else decided to throw a going away/birthday party for him. It was held inside the galley of his old ship that was now commanded by Ace who took over his old room. Out of everyone Luffy was the most emotional as he cried and said, "Why are you leaving? We're supposed to go out to sea together, remember? You're supposed to be my first mate!"
Marcus punched Luffy with his haki coated fist as he said, "I never said I would be your first mate nor did I say I would go out to sea with you! If anyone should be your first mate it's Zoro or Kuina."
"Huh? Why them and not me? Actually, why can't I be the captain?" Usopp asked as he glanced towards Marcus.
"Because I'm gonna be king of the pirates, so I have to be the captain!" Luffy said with his face surprisingly dry of tears now.
Marcus chuckled as Luffy and Usopp started bickering back and forth. The overall party was subdued with everyone wishing Marcus a safe journey. After the party finished Marcus ended up going onto the deck with Ace who he wanted to talk with. They stood next to the railing of the ship as they watched the full moon over the dark water of the bay.
Marcus broke the silence after a few moments and said, "You guys should head back and focus on training again."
"I was thinking the same thing since Sabo and I need more haki practice."
Marcus nodded before he said, "Go back to Cocoyashi Village and I'll have someone join you guys there to help with training."
"Who?"
"Someone who owes me a favor or two and can help train you guys in haki. I'll contact him after I set sail." Marcus said with a smile.
Ace frowned slightly since Marcus didn't elaborate before he asked, "Fine… You're planning to leave aren't you?"
Marcus smirked as he said, "I've already told everyone goodbye, there's no need for all of you to send me off. Besides, I've had enough of Luffy crying."
Ace shook his head as he said, "It's gonna be even worse if you leave and he doesn't get to watch."
"That sounds like a you problem." Marcus said with a smirk.
Ace punched Marcus in the arm as he said, "Dick."
After a few moments Ace pulled Marcus into a hug as he said, "Be safe little brother."
Marcus returned the hug as he said, "I'll be fine, I'm not a hot head like you who rushes into things without thinking."
Ace playfully shoved Marcus away as he said, "Fuck off."
They both stood in silence for a few more moments before Marcus said, "Alright, I'm heading out… Don't slack off on your training, I expect a decent fight the next time we meet."
"Don't worry, you'll have one." Ace said as Marcus clapped him on the shoulder before he headed towards his ship.
After Marcus left Ace headed into the ship and started ringing the alarm bell to get everyone's attention. Within moments everyone started coming out of their rooms and once they saw Ace he yelled, "Marcus is leaving! Let's go see him off!"
"What?!?" Half the crew asked at the same time.
"Is he trying to leave without saying goodbye?" Sabo asked with a frown.
"Marcus said he already did, so he didn't want us to send him off… But screw that, let's go see him off!" Ace said as he waved everyone outside.
Everyone rushed out of the ship and down to the dock to find Marcus as he removed the mooring lines for his ship. He was at the last one when Luffy's arms stretched out to grab him before he rocketed into Marcus. Marcus didn't try to dodge but was forced back by the blow before he glanced down at Luffy who was a blubbering mess of tears and snot. Marcus hugged Luffy back as he asked, "Why are you crying idiot?"
"You were gonna leave without saying goodbye!"
"I already said goodbye at the party." Marcus said as he glanced up at everyone who was now surrounding him.
"Jerk, you can't just leave without saying goodbye." Sabo said as he punched Marcus in the arm.
Marcus shook his head before he said, "I already did… But whatever."
Marcus smacked Luffy over the head as he said, "Let go you little cry baby."
"But then you'll leave!"
"Exactly! Now let go, you little monkey!" Marcus said as he tried to remove Luffy's arms from around his waist.
"No! I don't want you to leave!"
Marcus finished removing the last line from the dock before he coated his fist in haki and slammed it into Luffy's head. Luffy's grip broke as he slammed into the deck and Marcus jumped over to his ship as he said, "Someone hold Luffy so he doesn't get any stupid ideas."
Ace and Sabo helped Luffy up but held him in place as Marcus waved at everyone and said, "I don't know if I'll come back here, but I'm positive we'll all see each other again someday! Stay safe you guys!"
Everyone waved back and said their goodbyes as Marcus raised the sail and his ship started to pull away from the dock. Luffy who was still crying yelled out, "You better not join another crew! You're my first mate!"
"Shut up Luffy! I'm not gonna be a pirate!"
Ace covered Luffy's mouth as he said, "Stay safe and don't forget to call us!"
"I will… And make sure you head back to Cocoyashi Village in a couple days!"
"We're going back home?" Nami asked as she watched Marcus pull away from the dock.
"Yeah, we're going to be training more with someone Marcus knows."
Everyone watched as Marcus's ship disappeared from view before they finally headed inside. Marcus didn't waste any time after he left and skirted around the island before he checked his compass and corrected his course. Once he adjusted everything, Marcus moved the bicycle into place and engaged the drive train. It only took moments for Marcus to generate enough power for the ship to lift out of the water on its hydrofoils. The ship's speed was even more impressive than the smaller test ship and was easily double what it could reach with the improved design changes Frank made even with it being larger.
Through the night Marcus adjusted the sail and used the bicycle to speed towards the Redline. Early the next morning as the sun kissed the early morning sky, a massive red colored rock face loomed in the distance. Marcus didn't even pause to take in the view as he focused on where the entrance to the Grandline was. It was extremely close to the Calm Belt and the water around the area was extremely rough from the currents that pulled water up Reverse Mountain.
Marcus didn't need to search for long and he quickly found the iconic entrance. As he approached he quickly reefed his sail and let the main tidal current pull his ship towards the entrance. With the small width of his ship he didn't need to worry about anything and just kept a firm grip on the helm as he steered into the middle of the entrance. From there Marcus let the rushing water do all the work and as the boat entered into the channel leading upwards.
Within moments the boat picked up speed, but not as fast as a normal monohull ship would. Even so, Marcus started to pedal backwards on the bicycle to fight the current and slow down even more. He knew what was about to happen and while he trusted his boat, there was no need to damage it if it could be prevented. With that in mind, Marcus used the propellers to help slow the ship down and by the time it reached the top, it didn't fly through the air. Instead it reached the peak and gently floated out into the lake.
With one of his major concerns for the start of his journey out of the way, Marcus smiled as he turned towards the real entrance to the Grandline. For how fast the current leading to the top was, the lake at the top was pretty calm. Marcus studied each entrance for a few moments before he turned towards the exit path and steered his ship towards it.
Marcus didn't hesitate or waste any time as his ship entered the true entrance to the Grandline and headed downwards towards adventure. His first stop, Laboon and Crocus.