Earth-1

"This is how to stop the antimatter wave?" Barry asks when they entered the room to see a giant machine in the center of the room that has a red blur on a treadmill.

"This place is the nexus between your reality and the Anti-Matter. It's a reflection off of your technology but isn't it." Sarge expains. "This is the source of the wave." He says and that means if they stop it here, they stop the wave from hitting their world.

"Is that red blue moving, or is my eyes playing tricks on me?" Crystal asks the team.

"I'll check it out." Barry says while Sarge protests, Barry speeds up and sees its the older Barry Allen they met last year during the Elseworlds incident as he approaches the field, he gets hit across the room since keeping him on the treadmill.

"You all right, man?" Cisco asks him helping him back into his feet.

"Yeah, I'm fine. But that's the Earth-90 Flash on that treadmill. He's trapped." Barry tells them.

"That's Barry Allen from Earth-90?" Cisco asks, confused by how that's possible. "How'd he get here?"

"The Monitor sent him away to the netherverse where the Anti-Monitor found him and is using his speed to create his antimatter cannon. Test fired it and destroyed Earth-2." Sarge informs them.

"Jesse's gone? Frost is gone?" Crystal asks.

"Harry's gonna be enraged." Cisco states.

"How do we stop the canon?" Barry asks Sarge.

"The forcefield that contains this is antimatter based." Sarge tells him. "Anything made of positive matter can't penetrate it."

"We have to get him off the treadmill." Barry states and look to Cisco. "Think you can get him free, man?" He asks his Cisco.

"I'll give it a shot." Cisco offers and holds his hand out for a minute. They all wait for something to happen when a breach forms and frees Flash-90.

Barry goes to check on him as they watch the machine start shutting down without its speedster.

"Thank you for the reprieve." Barry-90 says to them. "But you have to put me back on it." He informs them getting everyone confused. Suddenly, the machine starts shooting lightning off in every direction.

"The Anti-Monitor put in a failsafe so if I ever got off of it, it would erupt, destroying all remaining Earths at once." Barry-90 explains.

"Sarge, how can we-?" Barry turns to ask the man but sees he's vanished.

-

Center of the universe

Peter keeps webbing around the room and flipping, connecting the webs together when one bundle starts sparking off, that must be his reality now starting to die off.

He webs through the bundle of webs, hoping he is keep this alive to give them enough time to save their reality.

-

Earth-1

Back in the antimatter cannon room, the lightning is getting worse by the second as it blasts around the room.

"It's getting worse." Cisco tells them.

"Put me back on that treadmill." Barry-90 tells them.

"No, well find another way." Barry promises when a portal opens and Strange steps through with someone new.

"Where am I?" The black man in a lightning style suit asks them.

"Now who are you?" Crystal asks with a whiny voice.

"Send me back to Freeland now!" He comands them before trying to blast them with lightning.

"Calm down, electric guy." Crystal tells to him.

"The names Black Lightning." He informs her.

Black Lightning tries another lightning bolt and Barry copies him and sends everyone flying around the room.

"Enough!" Strange proclaims to them all. "I didn't bring you here to fight, Jefferson, I brought you here to help us save this world."

"Strange, what the hell?" Cisco asks, getting back up.

"This is Jefferson Pierce, on his earth he's known as Black Lightning. An educator, father, and hero." Strange introduces him to the team. "Madame Web told me where to find him and we were going to need him from for what comes next."

"And who the hell are you people? And what do you mean my earth?" Jefferson asks Strange.

"You're from Earth-78, we're on Earth-1. As for your family, I had my assistant Wong bring them to this world where we relocated all the other worlds. Because your Earth and home...was just destroyed by a wave of antimatter." Strange informs the man.

"So-so they're safe?" Jefferson asks all that he cares about is his family.

"They're safe. I can assure you." Strange promises him. "But I had you transported here so you could help us save what's left of humanity."

"That machine behind you is the source of the antimatter wave." Sarge says as he appears again.

"What is with you and appearing like this?" Cisco asks after shrieking.

"We have to disable it but we can't get near it." Barry says. "Can you and the channel enough energy to steady it?"

Jefferson then scans the device and sees its power source and decides to try it to see if he can do it. He start summoning all of his energy and steadying the device so it won't destroy the multiverse in one sweep.

"Tick tock, people." Jefferson warns them while concentrating his energy on the device.

-

Waverider

Kara starts getting ready to use the book to bring everyone back when Kate stops her.

"Don't. You open that book, you don't know what's going to happen." Kate tells her.

"I have to, Kate. Those people, they need my help." Kara replies.

"And we are doing our best to help who we can." Kate tells her. "That is not the answer."

"Then what am I supposed to do?" Kara asks. "Just be okay with all those people dying? Like Bruce? Believe if life is supposed to end just let it?

"No, of course not." Kate replies. "But if you open that book, it will destroy you. Would Peter be okay with that?"

"Don't bring him into this!" Kara warns her.

"I'm sorry. Look, I wish I was as hopeful like you. But if you take a chance with that book and things don't turn out the way you planed, we're all doomed. Would Peter want you to risk the lives of everyone for him?" Kate questions. "What about your kid?"

Kara looks surprised she figured it out when they didn't have the chance to tell anyone. "You know?"

"Yeah, it was kinda obvious." Kate admits. "Do you think he would want you to risk your life and the child's life if would bring him back?"

Kara thinks and knows she's right, but she doesn't what her to be right. She wants Peter back. Not some doppelgänger of Peter, the Peter she was going to have a future with. The one that risked everything for them to survive.

She leaves Kate and the book, needing to think what to do.

-

Earth-1

Barry and Flash-90 start using FlashTime to buy themselves more time to come up with a plan.

"Every second that we waste here, another earth dies." Barry informs his double. "And that wave gets closer to my world and wife."

"I was married once, too." Barry-90 tells him. "Tina always said that keeping me running was her purpose in life, so as someone who's been running for 30 years, let me tell you. Sometimes, in order to find your purpose as a hero, you gotta take a couple steps back. Reverse the way you see the situation and see the bigger picture."

With those words, Barry gets an idea on how to stop the antimatter wave. Reverse the treadmill.

"I know how to stop the antimatter wave." Barry tells them. "We reverse the treadmills dimensional velocity." He explains the plan to them.

Cisco thinks of the plan for a minute and sees that could work. "Doing that could make the antimatter wave recede and funnel back into the speed cannon. Destroying the machine, and the wave."

"Ending this once and for all. And freeing Harbinger and Sarge from Anti-Monitor's control." Crystal finishes.

"Where's the future?" Jefferson asks like he's in some sorta trance. "Right here. Who's life is this? Mine. What are you gonna do with it? Live it. By any means necessary." He says confusing everyone.

"Cisco, Caitlin, you were the first people I saw when I first became the Flash." Barry tells his friends. "I wouldn't be the hero I am without you guys." He says before pulling them into a hug which they returned. "Open the breach."

Cisco does so and Barry speeds back onto the treadmill and starts running as fast as he can to stop the wave and the room starts to shake.

"We can't stay here, this whole place is coming apart." Strange warns them. "And the wave is about to hit us."

Cisco takes that as his que and opens a breach for them back to the Waverider.

Barry thinks back to the people who he's going to loose, and how many people he's saving by doing this. He starts flaking apart as he runs and destroys everything. Including himself and the antimatter wave as he shrieks...and vanishes in Crisis.

-

Center of the Universe

Peter finally stops swinging when he looks around and sees the dissolving webs stoped.

Panting heavily, he is amazed to see it worked. He helped saved the multiverse.

Then he looks and realizes there's only one bundle of webs left, meaning only one universe is left.

Now the question that remains is...how does he get out of here?

-

Waverider

Everyone returns to the Waverider and wonders what their next move is now with Barry gone.

Crystal changes into Caitlin quickly and finds Madame Web and hoped Peter was with her.

"Where's Peter?" Caitlin asks her, needing him right now.

"Still keeping the multiverse together, I'm on my way to..." Madame Web tells her when she suddenly stops.

"What's wrong?" Caitlin asks, seeing Madame Web staring off.

"Something...is wrong. We stop the antimatter wave, but I don't see any future. I should be able to see them all, but all I see is darkness." Madame Web says, wondering what they did wrong.

"What does that mean?" Caitlin asks, now afraid.

"There might not be a future." Madame Web guesses the most obvious guess.

"Well, that might have to do with the fact we don't have the last Paragon." Cisco said as he throws his gloves down.

"What?" Fitz asks. "What happened to Barry?"

"He destroyed the antimatter wave, causing it to kill him." Caitlin explains.

"So doesn't that mean we don't need the Paragons, right?" May asks.

"The Paragons are needed to defeat the Anti-Monitor. They don't stop the wave." Monitor explains to them.

"Well, what do we do now?" Deke asks. "If we need all seven, we only have six."

"There are more Paragons." Madame Web tells them. "We went for the first seven, but we picked backups in case something like this happened."

"Who is the backup Paragon of Love?" Barry-90 asks.

Monitor looks over to Daisy.

"What? Me?" Daisy asks.

"Daisy Johnson, you are the secondary Paragon of Love. You were brought here in case this were to happen to Barry Allen. Madame Web warned that this would happen, and we would need you if this was the outcome." Monitor expains why she was brought here, causing her to look shocked that she plays a role in saving the multiverse as well.

"So what's our next move?" Coulson asks the Monitor.