The trio of Batman, Penny, and Ben passed through the vent and into the old sewer system, a small distance away from a goon talking to Joker on a radio.

"Sorry, boss. It took a little longer to find him than you figured it would."

"Oh! I'm sorry. I'll try and be more precise next time I'm PLANNING AN ISLAND TAKEOVER!" The clown snapped from the other end.

"Hey, I didn't mean-!" The thug started before quickly being silenced by a strike to the back of the head.

"Helloooo? Anyone there?" Joker asked from the other end but was ignored as the trio continued down the sewer.

They continued through the waterways, stopping around the corner as they heard the chatter of some thugs further down the hall.

"Why are we the ones trying to open it? This ain't even the main door. If we even get it open, we don't know what it'll do."

"I ain't going near it, you even touch the door and it'll get you."

"Yeah, you remember Mickey, right?"

"He was an idiot. Deserved to be eaten."

"I say we just tell Joker we couldn't find him. We'll be safer. No one will know."

"Yeah, yeah! That'll work! No one'll know, it'll be sweet."

"Are we interrupting this conversation or can anyone join?" Penny wittily asked as she, Ben, and Batman made themselves known.

"It's The Bat and his two sidekicks!" One of the thugs cried in alarm.

After regaining their bearings, the goons charged the trio. Penny rushed in, jumping to the wall and pushing off it to punch a thug in the face, sending him to the ground, and uppercutting another one.

The thug that Penny knocked into the air with her uppercut was caught in a wind current by Ben, being spun around before getting thrown into two more of his buddies.

Finally, Batman threw a batarang to knock the last one down, rushing in and delivering a falling knee strike to the face to take him down.

"Man, that sucked...for them, not much for us." Ben joked.

"Let's go," Batman ordered as he continued down the path, Ben and Penny following him.

However, the path soon split to the left and right. Penny turned to the right door and suddenly saw the shadow of Killer Croc passing by, hearing his hateful guttural growl.

"I will find you. Rip your flesh like paper."

"Yeah, I don't think we want to go right..." Ben nervously muttered.

Penny nodded. "Indeed."

The three of them continued down the path, destroying a set of Joker's teeth before progressing down the narrow path.

"I've been digging deeper into Doctor Young. According to her bank records, there have been multiple payments from her project starting last April until 2 months ago. Then nothing." Oracle said. "The payments came from a company owned by a Mister Jack White."

"One of Joker's oldest aliases," Batman realized. "So, Joker pays Dr. Young to create his army and then all of a sudden stops. Doesn't make any sense."

They passed through the next area, which was some form of column structure with water running through several places. Ben couldn't help but whistle and admire the architecture, no matter how delipidated it was.

"So much history in just this sewer system."

"Indeed, it's quite fascinating!" Penny smiled.

"The area seems too unstable for us to grapple. We'll have to climb."

"Penny and I could just fly but...yeah, we don't wanna leave the professional behind," Ben smirked.

Batman didn't even dignify the boy's joke with a response as he suddenly got another call from Oracle.

"Hey! This is weird. The payments to Dr. Young's account didn't stop exactly, they were declined. Dr. Young put a block on her account."

"Sounds like she had a change of heart. She tried to block the payments." Ben realized.

Batman shook his head. "Joker doesn't like it when his partners try to back out."

Penny gasped. "So that's what this whole Arkham takeover was about in the first place!"

"Exactly!" Oracle concurred. "He decided to get himself back into Arkham, find his formula, and create the army himself!"

"You gotta be kidding me!" Ben exclaimed.

The trio began to climb the structure to get to higher ground as Oracle continued going over Dr. Young's files.

"I've hacked into her email account. Two mails stand out."

"Lay it on us, sister." Ben said.

"The first is a resignation letter dated last week. Sounds like she was trying to get away."

"And the second?" Penny asked.

"A message from Joker, well, Jack White. It's a long thread. She's begging to stop the experiments. Says it's too dangerous. He's not listening."

"Joker never does listen to other's complaints," Batman noted.

"Sheesh, and he calls himself a clown." Ben scoffed.

"Let's see, random threats to her family, a couple of bad jokes..." Oracle's voice then took a disgusted tone. "A picture of a dead baby and a threat."

Penny couldn't help but let out a silent gasp of horror at that while Ben felt a shiver run down his spine. Batman, for his part, just had a disgusted scowl on his face. Even after all these years, the Joker still managed to find ways to anger him.

"Go on."

"He says, I'm coming for you! I want what I paid for! And then another joke about wheelchairs, lovely..." Oracle continued. "And a drawing of some kind of donkey."

"Sheesh, if he was sending those letters to me, I'd be pissing my pants right about now," Ben muttered. "No wonder the poor woman's scared."

"I agree. The more I learn about Joker, the more evil I realize he is." Penny frowned.

"Trust me, you haven't seen the full extent of how evil he is," Batman warned grimly.

The trio reached the top of the sewer system. On the way out, Ben noticed a shining green question mark trophy and picked it up, looking at it curiously.

"Did Riddler leave this?" Penny asked.

"He's left quite a few of those around. It's his way of issuing a challenge."

"Who has time for that?" Ben pondered. "Seriously, what even is his deal? This isn't even a riddle, this is just a scavenger hunt."

"EXCUSE ME?!" Riddler's voice suddenly snapped over the comm. "I am the greatest mastermind in all of Gotham! The world even! I should be your top priority! I am the greatest threat you three could ever face!"

"If that's the case, then why aren't you coming down here and fighting us yourself or helping Joker with his little party games?" Ben sarcastically replied.

Penny giggled. "Oh dear, Ben, you're terrible!"

Even Batman couldn't help but smirk as Riddler spluttered to try and come up with a response before seething in fury.

"Oh, I'll come up with something special JUST FOR YOU."

"I look forward to it. If it's as easy as finding your stupid trophies, I'll probably have a blast!"

"Impressive. You've gotten under Riddler's skin. He'll be fuming about that for a while." Batman said. "We shouldn't hear from him again for some time."

"I should hope not. His behavior does not sit well with me." Penny said.

The trio headed down a narrow path, going through another door and ascending a flight of stairs, and turned right, following the path until they seemingly hit a dead end. Batman took out his Explosive Gel and used it to blast the wall open, revealing a path with a hole in the ground leading to a black abyss between them and the path. However, it was easy enough for the three of them to jump across.

"Ah, fresh air!" Ben said as he opened the door in front of them and felt the night breeze hit his face.

"There's no time to sit around and relax now. We have to get to the mansion. Cash and Doctor Young could be in danger and worse yet, Joker could have the formula. And there's no telling what dangers he left for us along the way." Batman said ominously.

"Then let's make haste!" Penny said urgently.

Does anyone else agree that the Riddler Trophies kinda don't make sense from a plot perspective? I mean, what's the Riddler's deal with them anyway? It's not like they have some sort of connection to the riddles he dishes out.