Minutes later after the battle with Black Manta in Italy, Arthur slowly opened his eyes and woke up on a boat. After Arthur got rid of the bandages and seaweed on him, he put on a long-sleeved shirt and walked towards his friends at the front as Mera played her musical instrument, a soprano recorder, to play a peaceful song while the Ninjas watched and listened.
Rarity complimented, “What a beautiful song, Mera.”
“Thank you.”
Arthur asked them, “Did you guys steal a boat?”
“Are the boats at the marine not for public use?” Mera asked him back.
“No. Those belong to people.”
“Now do you understand why the boat driver was chasing us with that shotgun earlier?!” Twilight told her.
“Huh,” Mera understood while Arthur chuckled. He sat down with the gang as she continued, “Those were Orm's elite commandos. But the one who led them wasn't Atlantean. I've never seen him before.”
“Yeah, well, I have,” Arthur admitted. “He and his father were pirates. And he blames me for his father's death.”
Mera told her husband, “They picked a dangerous line of trade. It's not your fault.”
Leo commented, “Even if you did it, actions have consequences.”
Mikey nodded, “Yeah, he's got no one to blame but himself.”
“That's not how it feels,” Arthur said.
“What do you mean, Arthur?” Pinkie sadly asked him.
“Yesterday, I stopped them in the submarine. However, it was going to sink because of his firearm. It was up to me, and I let him die. I could've saved him, but I didn't. And now, I made an enemy, and he could have hurt you. And that would have been my fault.”
While the Atlantean couple took their time to reflect, Twilight told him, “Everybody makes mistakes. Don't let that get to you.”
“She's right, he's behind us now. It's what lies ahead that should concern us,” Mera said.
The teens and Arthur wondered as Casey asked, “Uh, what's concerning about the path we're taking, Mera?”
Mera explained, “The charted path leads to the Kingdom of the Trench.”
“The Trench? You mean the home of those same creatures that killed my mother?” Arthur questioned her.
Mera nodded, “Yes. She was taken there and sacrificed to them.” The Ninjas gasped as Mera continued, “It's become a place of death. We know next to nothing about what lies down there.”
Then Mikey called, “Hold up. Time out for a second y'all. Can you explain to us what exactly are the Trench?”
“You know, these guys are from another dimension and they don't know exactly the stuff that's common here in this dimension. So, can you go ahead and tell them please?”
Mera sighed, “All right. The Trench was originally one of the tribes of Atlantis. But when it sunk beneath the waves, they didn't advance but devolved, turning them into mindless animals. The Trench is used as a form of execution by our kind.”
Mikey groaned, “Aww man, I feel sorry for those people now. I wish they were nice.”
Rarity stuttered in fright, “M-maybe we should turn back. We can still warn the citizens on land. Try and prepare for what's coming.”
Casey, Mikey, and Pinkie agreed with Rarity and Mera replied, “Turn back? We can't turn back now, Rarity.”
Leo noted, “She's right. This is the only path we have to get to Atlan's trident.”
“Fine,” Rarity sighed, but felt nervous.
Arthur sighed and told everyone, “Let me tell you all something about me. I learned from a young age not to show weakness. Okay? I solve my problems with my anger and my fists. I'm a blunt instrument, and I am pretty good at it. But I've done nothing but get my butt kicked this whole field trip. I'm no leader. I'm not a king. I do not work or play well with others. And I can't let all of you die trying to turn me into something that I'm not.”
“You think getting defeated over and over doesn't make you a great leader? Well, if that were true, then I wouldn't be the leader of my team right now,” Leo replied.
Mera and the rest of the gang understood Arthur’s pain inside him. She told him, “You think you're unworthy to lead because you're from two different worlds. But that is exactly why you are worthy. You are the bridge between land and sea. Atlantis isn't the same without you. I need you back. Our son needs you back because I believe that he wants you to be the father that he can look up to. I can see that now. But the question is… Can you?”
Arthur looked at Leo’s team and they gave him supporting smiles while the boat continued sailing to the charted path.
Meanwhile, at Orm’s ship, Vulko approached his king and informed him, “The tracking on Lady Mera is still dark, Your Highness.”
Orm nodded, “Vulko. My trusted vizier who has stood by the throne since my father sat upon it. Do you have any advice for me as this war begins?”
“I have already given it, My King. But I will stand by your decision, as always.”
“My decision. To protect it.” Then, the mood quickly changed when Orm frowned, “While you betray it.” Vulko became surprised as Orm continued, “You think I do not know of your treachery? That you remained loyal to my mother's wretched son. That you have spent years training him to take the throne from me,” Orm glared daggers at Vulko as Orm’s royal guards entered. “Do not deny it.”
Vulko became afraid of what would happen if Orm found out about his treachery. He told the truth, “I do not.”
“Why? I am the pureblood. I have devoted my life to Atlantis. He wanted nothing to do with it. You swore to serve the throne!”
Vulko told him, “Arthur may be half-Atlantean, but he'll be twice the king you'll ever be.”
Orm smiled as if it was a joke, “Take him, but make sure he has a view.”
While the guards took Vulko to his prison area, he thought to himself, ‘I hope Arthur's new friends got my message.’
Meanwhile, Raph and Rainbow were being scolded by their teammates in the Turtle Sub as they continued travelling.
“What were you guys thinking?!” April shouted. “You could've gotten yourself killed out there!”
“It was better than seeing an innocent man die by a coward!” Raph stated.
Rainbow added, “We can't just let Orm get away with his plan. We have to stop him.”
Raph questioned her, “How?! We are outgunned and we have only half of our group because Arthur, Mera, and Leo’s team doesn't have the trident yet! How do you expect us to fight Orm and his army?!”
Donnie answered, “Hey, settle down you two. Now according to Vulko's message that we received earlier, we need to get to the Brine Kingdom and try to convince their king to help.
“How in blue blazes do we even find it, much less convincing the king,” Applejack responded.
Sunset read the scroll that Vulko sent them earlier, “Vulko’s message says that he's sending someone to help.”
“Who’s he sending?” Fluttershy asked.
Just then, the group felt something swimming past their sub at top speed, causing them to spin for a bit, but stopped suddenly.
“Whoa. What a ride,” Rainbow commented, feeling a bit dizzy.
The group turned to see an Atlantean and a small amphibian-humanoid hybrid floating outside, facing them.
“I'm guessing it's those guys,” April pointed her hand at the Atlanteans.
Raph questioned everyone, “How do we know we can trust them?”
As if they heard the turtle, one Atlantean with black hair showed them a yellow circular device with a "T" on it. The ninjas instantly recognized the logo and knew what it meant.
Fluttershy happily gasped, “He's a Titan!”
April cheered, “A Teen Titan? That's great. Send him in here.”
Everyone carefully opened the entrance to the Turtle Sub and two Atlanteans entered inside. The two Atlanteans entered the control room while the Atlantean dude whipped his hair back and forth in slow motion, making Fluttershy and April attracted to him.
Sunset greeted him, “Sorry for the wait. Not all of us can breathe underwater.”
“It's all right. I understand. My Atlantean name is Garth, but my Titan friends call me Aqualad. It's very nice to meet you all.”
The amphibian spoke in Atlantean language, but the Ninjas could not understand him.
Applejack commented, “I cannot understand what he just said.”
Aqualad informed everyone, “My apologies, this is my friend, Tramm. He's good with tools.” Aqualad and Tramm shook hands with everyone. He continued, “Nightwing and his pals told me and the rest of Titans East all about you guys helping out in Gotham and Jump City.”
“Uh, yeah, we sure did,” April continued shaking his hand while being distracted by Aqualad’s handsome face.
“Ahem!” Donnie shouted, feeling jealous. “You can let go now, April.”
Raph commented, “Wow, there's a form of irony if I've ever seen one.”
“Huh?” Aqualad wondered.
“I'll explain later,” Raph continued. “Right now, we need to warn the Brine Kingdom of the attack. Can you guide us to the Brine Kingdom?”
“I sure can, my aquatic friend. My Atlantean friends and I are good pals with their king. He'll listen to us.”
Aqualad exited the Turtle Sub while Tramm stayed behind. Aqualad contacted the Ninjas with the earpiece that Donnie gave him and his pals earlier. “Follow me.”
While Fluttershy and April were distracted by Aqualad, Donnie snapped out of his jealousy and resumed control of the Turtle Sub, following the Atlantean to the path. However, a huge shadowy figure with fins watched behind the rocks.
Minutes later, something swam past the Turtle Sub in the shadows.
“What was that?” Raph wondered.
“Not sure, but we'll keep an eye out for what's coming.”
Then suddenly, the Turtle Sub was blasted by a small energy beam.
“We've been hit!” Donnie alerted everyone.
“By who?” Fluttershy asked.
Applejack looked from the window and saw an Atlantean with a trident. She pointed out, “Him.”
Aqualad did not take long to figure out who attack them and it was a foe from his past.
“Well, well, if it isn't my good ol' pal, Trident,” He sarcastically said. “Seems like Orm released you from prison.”
“You bet he did.” Trident contacted Orm with his communicator, “King Orm, I have the targets in my sight.”
“Good. Do whatever you want with them, just make sure they don't get to the Brine Kingdom before me. There's a bonus payment for you if you bring Aquaman's sidekick to me. Dead or alive.”
“With pleasure,” Trident acknowledged.
Donnie contacted Aqualad, “Seems like you know this guy very well, Garth.”
“Yeah. Trident is the worst kind of criminal in Atlantis.” Aqualad then informed the Ninjas, “You guys go ahead. I got a score to settle with Trident for nearly putting my Titan friends in deep six.”
Just then, Raph and Rainbow came out with their diving gear on.
“Let me help!” Raph said.
Rainbow called. “Me too.”
“By all means. Let's go get him!” Aqualad ordered and the three heroes set their sights on Trident.
The Turtle Sub swam away from the battle to get to the Brine Kingdom until they are met by an army of Trident clones.
“Y'all have got to be kiddin' me right now,” Applejack exclaimed. “How many Tridents are there?”
“Looks like he cloned himself into an army, but it's weird,” Donnie guessed.
“Now taste the full might of Trident!” The Trident clones announced and charged right at the Turtle Sub.
“Here they come!” Sunset shouted.
Then, a big mutant shark swam past the Turtle Sub and sent a big shock wave with a clap of his hands, saving the Ninjas.
The Trident clones were knocked off by that shock wave, but it wasn't enough to knock them down.
“Is that a mutant shark, with shorts?” Donnie wondered.
April commented, “And he's not much of a threat like Armaggon.”
The big shark creature turns around and… waves at them.
“It's waving at us.” Sunset noticed, wondering what the shark is up to.
The Ninjas nervously waved back at the shark creature.
Then, one of the Trident clones charged straight ahead while the shark creature was distracted.
“Behind you!” Donnie shouted.
The shark creature turned around as the Trident clone was heading closer. However, Fluttershy wore her scuba gear and came to his aid by shooting the Trident clone with a dart from her blowgun. The Trident clone felt woozy until he was knocked out.
“Are you hurt?” Fluttershy asked the big shark guy.
The big shark creature shook his head.
Fluttershy then noticed the sad look on the shark’s face, “What's wrong?”
“I have no friends,” The shark creature answered.
“You don't have any friends?” Fluttershy gasped.
The shark creature shook his head in response. In return, Fluttershy hugged the shark creature out of sympathy.
“It's okay, big guy. I'll be your friend.”
The Ninjas were confused while witnessing Fluttershy hugging the shark creature.
April, Sunset, and Applejack responded, “Aww.”
Raph said, “I am SO confused right now.”
Then, the Trident clone army returned to charge after the Ninjas and the shark creature. One of the clones said, “Take them all down!”
“They're coming back!” Donnie shouted.
Fluttershy and the shark creature saw the clone army and stood their ground until a couple of Trident clones were blasted by energy beams.
“What was that?” Donnie asked.
Coming to their aid were three more Atlanteans as Tramm jumped for joy in the Turtle Sub. One of them was a girl, the other was a dude with light blonde hair, and another was an amphibian creature like Tramm.
“Attack!” The Trident clone ordered and the rest of the clones attack the Turtle Sub and three more Atlanteans.
“You mess with our friend, Garth. You mess with all of us.”
The Atlantean girl responded, “You got that right, Kaldur. La'gaan, show them what we got.”
“With pleasure, Tula.” La'gaan nodded and enlarged his body like a pufferfish.
Raph and Rainbow looked up to see three more Atlanteans joining the fight with the Turtle Sub.
“And who are those guys?” Raph asked Aqualad.
Aqualad answered, “My friends.”
“La'gaan, throw me,” Kaldur signalled and La'gaan tossed him with incredible speed by the use of his super strength. Kaldur then used his sorcery to create weapons like swords by solidifying water and attacked the Trident clones with it. Tula then used her sorcery to attack some more Trident clones.
Sunset informed her friends, “Donnie, April. Applejack and I are heading out of the Turtle Sub.”
Donnie replied, “Good call. We want to make sure our new aquatic friend doesn't touch anything in here.”
Tramm waved his hand to everyone and answered in Atlantean language, “Okay.”
Sunset and Applejack put on their scuba gear and joined the fight with their ninja weapons alongside Fluttershy, Kaldur, La'gaan, Tula, the Turtle Sub, and the big shark creature. Back to Aqualad, Rainbow, and Raph, they continued fighting against the other half of the Trident clones, but they were still outnumbered.
“There's too many of them!” Raph exclaimed.
“I know,” Aqualad replied. “Hey, which one of you is going to bring me to Orm? He might pick a favourite.”
“I'll be the one to bring you in!” One Trident clone said.
Another Trident clone replied, “No, I am!”
Rainbow chuckled, “Now this should be entertaining.”
After the Trident clones continued arguing, they started fighting each other while Raph, Rainbow, and Aqualad watched them fight. Minutes later, the Trident clones were defeated.
Rainbow commented, “Well that was unexpected.”
“Except for one,” Aqualad pointed his finger at the last Trident clone.
Trident scoffed, “Don't think this is over yet, Garth.” He charged right at Aqualad until the rest of the Ninjas, Atlanteans, and the big shark creature came to aid Raph, Rainbow, and Aqualad.
Tula and Kaldur used their Atlantean sorcery to tangle Trident with water-like construct tentacles.
“Seems like you've been busy, La'gaan,” Aqualad noticed.
“Yeah, but we manage to defeat the other half of the Trident clones thanks to these guys,” La'gaan replied and mentioned the Ninjas with smiles on their faces.
“Orm and I will not forget this!” Trident swore. “Mark my words, you will all pay and beg for mercy when Orm succeeds in his mission.”
Aqualad ordered, “La'gaan, send him packing.”
La'gaan nodded and enlarged his body again. He then grabbed Trident and threw him far away from the heroes, never to return.
Applejack said, “Glad, that's over.”
Aqualad then noticed the shark creature, “Wait, why is Nanaue here?”
Fluttershy spoke up, “He saved us.”
“What?” Aqualad and his pals replied.
Donnie supported Fluttershy’s statement, “It's true. This big shark saved us from the Trident clones.”
Nanaue lay down and laughed while making a sand angel for fun.
Sunset informed everyone, “Um, let's talk about this later. Right now, we got to go to the Brine Kingdom. Pronto.”
“Agreed. Follow us,” Kaldur ordered.
The Atlanteans and Nanaue resumed guiding the Ninjas to the path to the Brine Kingdom.