Prologue:
He was not a villain, not with his lovely wife Nora back with him despite the fact that there was no cure for his need of zero or below temperatures. However, sometimes Mister Freeze came out of retirement for special events like today. So he was creating havoc, as requested, at Gotham Central Park by terrorizing those celebrating the 4th of July. He froze a couple stunt-people and a few grills until an exploding batarang hit his gun and knocked his aim so he froze a tree.
"Batman." He rasped, "I was wondering when—"
There was a mad cackle, high like a hyena's laugh but sweet like a bird song.
"Oh, Boy Wonder." Mister Freeze breathed lazily, catching sight of his young foe, "The Bat sent you to drag me off to prison. Frankly, I'm underwhelmed."
"Great." Robin replied, ""But I'm kinda in a hurry here."
"Kids, always in such a rush. I prefer to preserve these moments forever." He took aimed but made sure to only come close to freezing the boy. Robin dodged agilely, biting back, "I wasn't talking to you."
Nightwing fell upon the villain, disengaging the mobility of his exo-suit before jumping away.
"We'll call Nora for you Freeze, and then the police!" the elder vigilante told the villain as he and his sidekick bounced off. Sneakily Nightwing touched the Bluetooth earpiece he wore and told his mentor, "We got him Bruce, send in the police."
"All according to plan?" Bruce asked.
"Yes. Operation No Sidekicks is a go."
Over in Happy Harbor Aquaman and Aquagirl had barely made it from their front yard before their villain appeared. Killer Frost was causing mayhem.
"Do not tell me you are not excited." Kaldur'ahm said to his daughter as they fought their foe.
"Right now Dad I'm more focused on getting this shot!" Nerissa replied, using a Greek Fire bomb arrow. She was perched on top of a car as she took aim and let it fly, flipping off the car as Killer Frost tried to freeze her.
Killer Frost went down easily, the fire taking her ice powers and rending them unusable. Nerissa grinned, "Yeah, I'm excited. Today's the day."
In Keystone.
"Seriously," Wally spoke with derision as he and his cousins whipped around their frienemy, "stealing ice. Isn't that a bit cliché even for you CC?"
"Have to train the newest generation, start with the easy stuff right?" Captain Cold shrugged, "Right Crystal?"
Crystal Snart was Leo Snart's (aka Captain Cold's) ten year old daughter. She was just learning the Rogue-craft, having just taken the mantle of Kid Cold.
She smiled and waved, from her perch atop an ice mountain, asking, "Am I really scary Uncle Wally?"
Wally smiled warmly, "Oh yeah sweetheart, I'm very scared,"
"C'mon we don't have time for this!" the Tornado Twins spoke in unison, rolling their eyes and zipping around Captain Cold to melt his perch and then used his own gun to freeze him from the neck down.
Soon the sirens of the police came but the Tornado Twins were much more concerned about getting their mentor to leave, "Calm down, Kids!' Wally laughed.
"Puh-lease! You'll chat it up with the cops, with bystanders, with Cold even!" Kid Flash said.
"No! No way! Today's the day!" Impulse finished her brother's thought as they rushed their cousin.
They made it to the Hall of Justice to find, "Ugh. We knew we'd be the last ones here!"