Demigods: In Paris (a Miraculous Ladybug and Percy Jackson crossover)

Tidal Wave makes an appearance

Almost as soon as Ladybug disappeared off the rooftop, Gabriel had fastened the tie pin back to his collar.

"I wouldn't do that if I were you," Percy warned, Riptide at his throat before he even finished speaking. Gabriel swallowed. Nooroo whimpered.

Then Gabriel brought a hand quickly up to bat the flat of the blade away from his throat, and his hand went through the blade. He tried again, then laughed. "It's an illusion! Nooroo, dark wings rise!"

"Hey, Gabriel, let's talk about this," Percy tried to reason, but the man just grinned behind his silver mask. Hawkmoth swung his cane at Percy's head, clearly hoping to knock him out, but Percy caught it before it impacted and yanked it out of his grasp, wielding it like a sword. 

"That, was rude."

Hawkmoth stood his ground as Percy advanced, and threw two punches. Percy dodged the first then deflected the second with the cane, but tripped over the following low kick, unused to fighting on the uneven beams of the Eiffel Tower. Before Hawkmoth could push his advantage, Annabeth jumped into the fray, swinging her bone sword.

"Is that an illusion too?" Hawkmoth sneered.

"Why don't you come and find out?" Annabeth asked sweetly, slashing at him. Hawkmoth danced back, not willing to take the chance. Percy got to his feet in time to see Ladybug arrive back on the rooftop. Hawkmoth lunged at him, and he threw the cane at him like a javelin. He ducked, and it skittered to the ground. Hawkmoth lunged after it, allowing them to discuss quickly with Ladybug.

"I left Adrien somewhere safe. You need to help me take the Butterfly miraculous."

"Okay. How-"

Hawkmoth's laugh cut them off. In his hands was a black butterfly.

"No!" Ladybug breathed.

 "For too long, I've bestowed power on others. Now it's my turn! If I cannot take your miraculous, if you will not give me your miraculous, then I will prise your miraculous off your dead body!"

He released the butterfly, and Ladybug shot her yo-yo, but Hawkmoth swiped the butterfly out of the air, absorbing it into his arm. The yo-yo bounced harmlessly off his hand. The villain cackled in delight as the inky purple cloud engulfed him, and he emerged looking mostly the same, but with a purple whole-face mask instead of the silver one that left his mouth exposed.

Without warning, Hawkmoth flung his hand out and three somethings span out from it. Annabeth ducked, narrowly avoiding one object, and it embedded itself in the steelwork behind her. Keeping an eye on Percy to make sure he was distracting Hawkmoth, she tugged it out. It looked like the butterfly miraculous, but the four wings extending from the purple gem were deadly blades. As she examined it, in was swallowed by a purple cloud like the one that had covered Hawkmoth, and vanished. Annabeth saw it reappear in Hawkmoth's hand.

"Duck!" She yelled, and Ladybug did as she was told just in time to avoid a lovely new forehead piercing.

"Now might be a good time to summon Medusa again," Percy yelled as he ducked under a swing of Hawkmoth's staff.

"On it!" Ladybug called back. "Lucky Charm!"

A kettle fell out of the sky.

"Not helpful!" Percy yelled as he was knocked back, and Annabeth moved into the fray to let him catch his breath.

"I know what I need to do!" Ladybug called back. "Can you two handle him for a bit? I'm going to get some backup!"

"Hurry!" Annabeth yelled as she opened a cut along Hawkmoth's stomach that sealed again almost immediately, then dodged a sharp butterfly.

Ladybug swung away, and Percy joined Annabeth again as they kept Hawkmoth engaged. 

"You can't win!" Hawkmoth snarled. "I have powers, what do you have? A sword that doesn't work? Give up, and I'll let you live!"

"And stand back while you kill our friends? I don't think so!"

"You should consider what Ladybug told you!" Annabeth grunted as her sword impacted against Hawkmoth's staff and she pushed him back a step. "She has a point!"

"Everyone's lost someone they love," Percy agreed as he dodged several pointy missiles, thinking of Bianca and his other friends that had died. "We've both lost family. Trust me, sometimes they don't want to be brought back."

"Fools!" Hawkmoth hissed. "You have no idea what it's like to have such power!" He lashed out at Annabeth, opening a shallow gash along her cheekbone. "I WILL bring her back!"

Percy scowled as Annabeth cried out, touching her cheek before launching a new offensive. Every wound she inflicted on the villain healed over immediately, but she wasn't aiming to injure him. Whilst she distracted him, a wave of water rose up behind Hawkmoth. He turned at the last moment and screamed as it rushed down on top of him.