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AN: The last chapter of this story is here, and I hope you like it.

Mercurial

"So… you got your powers in the Second World War?" Cisco stared incredulously at Captain America, the various members of Team Flash looking incredulously at the Avengers while Wells examined the mask worn by Hunter's mysterious prisoner. "How… I mean, wow…"

"Didn't we have something like that in this world?" Barry looked at Cisco in surprise.

"Yeah, but from what I've heard our version pretty much drove everyone who used it insane; doesn't really count as a scientific success," Cisco clarified.

"In defence of your world, the only other person who was exposed to the same process as I was did go insane, and he was disfigured by it as well," Steve noted.

"Disfigured?" Jessie asked. "How?"

"His head looked like a skinless red skull."

"…Yeah, that's just gross," Cisco noted, wincing at that image. "I mean, intimidating, but gross."

"Isn't Bruce's transformation based on that process as well?" Barry asked. "I mean, I did a bit research on your histories while I was in your world…"

"I used a variation of it, but… I got a few things wrong," Bruce shrugged, standing awkwardly at the side of the room in a loaned STAR Labs hoodie after the destruction of his own shirt. "Different power source used to kick-start the final process, maybe missed a couple of the details of the serum itself… people have theorised for years that the scientist who created the serum made a few last-minute changes the night before Steve's process and never wrote anything down, so compared to some of the other attempts, I actually got off fairly lucky."

"I… see," Caitlin nodded thoughtfully.

"And what was that thing you used to turn back?" Cisco asked. "I mean, the hammer-guy just showed you that phone, and you-"

"It's private," Bruce and Steve said at the same time, each man looking slightly uncomfortable at the topic.

"Oh… sorry," Caitlin said, nodding in awkward understanding before she looked at Steve with a more curious expression. "Getting back to your abilities, I take it there aren't any samples of your DNA from before this… super soldier process changed you?"

"Not as far as I know," Steve said. "Why do you ask?"

"Just curious," Caitlin clarified. "If your world had prior samples of your blood, they might have been able to properly reverse-engineer it by comparing samples from before and after the change…"

"On the topic of powers," Jessie glanced around the Avengers before her gaze fixed on Pietro, "how exactly did you get here if you're not… well, from what Barry told us earlier, you're not linked to the Speed Force like he is?"

"Correct," Pietro nodded. "Barry and our scientists back home think that, as I do not draw on this 'Speed Force' you talk about, I cannot create rift myself, but can travel through existing one if I move fast enough."

"So you just… ran quickly and followed him through the rift before it closed?" Caitlin mused. "That… makes sense."

"Yeah, I carried Steve and Pietro carried Bruce," Barry put in, indicating the fourth Avenger with a smile. "Thor here has… some experience with crossing dimensions; he said he could follow me on his own steam."

"You travel dimensions?" Cisco looked at Thor with a newly-eager smile. "Does this have something to do with the whole… 'god' thing?"

"It ties in to how the Earth my companions and I come from worshipped my people as gods in the distant past, if that is what you mean," Thor acknowledged. "I have officially abdicated from the throne of Asgard, but I retain sufficient authority to command the attention of Heimdall, he who guards the Bifrost bridge that allows for travel between the realms, and he was able to extend its influence to follow Barry Allen's request for help."

"Huh," Cisco said, looking thoughtfully at Thor for a moment before he smiled. "From what I understood of that, it's pretty neat."

"You know what I don't get?" Wally put in, looking curiously at Pietro. "You said that you and your sister got powers from this thing called the Mind Stone… I can get how that ties in with what you've told us about her powers, but what does being fast have to do with something that should give people mental abilities?"

"The psychological acceleration, for one thing," Caitlin clarified.

"What?" Wally and Pietro said at once.

"Well, a speedster's mind has be accelerated to keep up with the new sensory input they're receiving when they run, or they'd just end up running into a wall or something the first time they moved above human speeds because they'd lose track of what their bodies are doing," Caitlin explained. "In Pietro's case, this 'Mind Stone' much have accelerated his mind to a level where he could safely move at superhuman speeds as well as giving his body the ability to move that fast in the first place."

"That makes sense," Pietro nodded, smiling briefly at Caitlin.

"Ugh!" a new voice suddenly said, the assembled heroes and their allies turning to where the man in the mask walking down from the room where Harrison Wells and Cisco had been getting him out of the mask. "I don't know what's more annoying; being in that thing, or listening to you two arguing about it."

Turning around to look at the now-unmasked man, the Avengers were just casually interested at the chance to see the mysterious prisoner's face, but Barry and his allies were left staring incredulously at the sight of a man they'd seen die just a few days ago standing among them as though nothing had happened, albeit dressed in a manner that they'd never seen before.

"I'm Jay Garrick," the man said, displaying a shabby beard and a dirt-stained face. "The real Jay Garrick."

After a moment, the Avengers realised that all of Barry's allies were currently looking at the traditionally-red-clad speedster in obvious apprehension, as though theyw ere expecting some kind of breakdown.

"What?" Garrick asked.

"I'm sorry," Barry said weakly. "I-I'm sorry…"

As his fellow speedster left the room, Pietro quickly moved after him, barely registering Iris following him as they soon found Barry further down the stone corridor, body shaking with sobs as he crouched on the floor.

"Barry?" Pietro asked.

"He… he looks just like him," Barry said

"'Him'?" Pietro repeated.

"Jay Garrick looks exactly like Barry's dad," Iris explained.

"His dad?" Pietro repeated, suddenly remembering what Barry had told them about Zoom when he came to ask the Avengers for help. "Oh God… I am sorry, Barry."

"It's not your fault-"

"But I can imagine how you would feel," Pietro said.

"You lost your dad?" Iris looked at Pietro curiously.

"My parents were killed when our village was bombed," Pietro replied. "My sister and I only survived by a supposedly impossible chance when one bomb never went off, and we spent the next few days waiting for it to detonate, too scared to even move in case we or shifting rubble brought it down on us, before we managed to escape."

"Oh," Iris said, looking sympathetically at the other speedster before she looked back at Barry. "But Barry… if he doesn't know who he is to you… you want me to tell him that you just had to leave?"

"No," Barry said, standing up even as his posture shook in the process. "No, I can do this."

"OK," Iris smiled at him.

"I'll just be a minute," Barry nodded.

"And we're here for you for that minute," Pietro said, sitting down beside his fellow speedster.

"There was a dampener in this thing that stopped you accessing your powers?" Bruce said, studying the severed metal mask that had been covering Jay Garrick's head.

"Exactly," Jay said, glaring coldly at the mask that he had just broken in two with one vibrating hand. "He stole my name, my colours… the only thing that was him was that helmet."

"I wondered," Pietro said, studying the silver bowl-like- helmet with small golden wings on a nearby table. "What is this?"

"He said it was his father's from the war," Iris said.

"Ironically," Harry observed, picking up the helmet from the table, "on my- on our Earth, this helmet stood for hope."

"Yeah?" Jay looked curiously at the scientist.

"Yeah," Harry confirmed.

"Well," Jay said, looking thoughtfully at the helmet as he walked up to Harry. "Maybe I can continue that sentiment… take something from him for a change and make it my own."

"That could work," Bruce nodded, as Jay took the helmet from Harry and put it on his head

"It suits you," Caitlin noted.

"Thank you," Jay said, looking around the room. "All of you, for saving me from Zoom… especially you, Flash."

"You're welcome… Flash," Barry replied, smiling awkwardly back at Jay.

"You deserve it, Barry," Steve nodded at the younger man. "Remember; you're an Avenger."

"I just fought with you guys once-" Barry protested automatically.

"Twice," the four Avengers corrected him simultaneously.

"And you joined us the first time to save a world you didn't even know from a threat that you'd had nothing to do with," Steve continued. "You've suffered a great loss, and I'm sorry about that, but if you take anything away from this experience, Barry, remember this; two different Earths consider you one of their mightiest heroes."

"And the residents of two more Earths are proud to know you," Jay added, smiling at Barry in approval, Harry's brief nod somehow the greatest sign of acknowledgement that man would ever give him.

"Th… thanks," Barry said, lost for anything better to say as he looked at this man who was so like his father even as he clearly wasn't. "You know… you helped me even before you got here."

"We did?" Bruce asked. "How?"

"When he… killed my dad," Barry said, swallowing down the pain as he looked at Bruce, "Zoom said that he was doing it to prove his own strength and make me like him… and I used you as an example of how he was wrong."

"Me?"

"Well… you saw your dad kill your mom when you were younger than either me or Zoom, and even as the Hulk, you've never taken that out on anyone who didn't deserve it," Barry explained, grateful that Bruce just gave him a sympathetic smile despite the personal nature of this discussion. "I just… Zoom was ranting about his own strength, and I just told him that all he was doing was lashing out at the world because he couldn't cope with his anger any other way, letting his life be defined by one event when you never let what happened with your parents define your own life."

"I still went into the same field of research as my dad-"

"But you didn't end up… well…" Barry said, trailing off before he could label whatever was wrong with Bruce's father. Bruce might have basically hated his father, but considering that the human Hulk never talked about his parents to anyone as far as Barry could tell, bringing them up in depth would just be awkward at best even if it was to make a positive point. "My point is, you all showed me proof that the strongest decision when wielding power is using it to help others; using it to break stuff like Zoom or Ultron did is just the easy option."

"It's something we all need to remember sometimes," Steve reflected. "We've all endured a great deal to become what we are now, but the important thing is that we work out what we're going to do with ourselves now that we have this responsibility, and keep on being strong enough to use it to defend the powerless."

"And what if you can't?" Barry said, looking at the Avengers' leader with a new sense of uncertainty in his manner. "What if it's just… right now, I just feel…"

"Broken," Bruce finished, shooting a look at Jay that made it clear his own involvement in this conversation wouldn't be welcome no matter how well-intentioned it might be, before he moved over to stand beside Barry and place a reassuring hand on his shoulder. "You showed me that I couldn't just run away from my problems and fears with the other guy; what makes us Avengers isn't that we never fall down, but that we pick ourselves up after we take that kind of beating."

"And if you can't?" Pietro said, smiling at Barry in a half-teasing manner. "It's like the captain said; walk it off."

Looking around the room at the other heroes, Barry finally smiled gratefully at them all.

"Thanks," he said at last. "I… I needed to hear that."

"Do not define yourself by what you have lost, Barry Allen," Thor put in now, Mjolnir hanging by his side as he addressed the young speedster. "Remember the obstacles that you have overcome to reach this point, and be assured that you can overcome the ones you face now and those which are yet to come."

"Exactly," Jay smiled at Barry. "One of the first things you learn as the Flash, Barry; we may still stumble like everyone else, but we get up faster than everyone else when we put our minds to it as well."

"Right," Barry nodded at Jay, his smile becoming slightly broader at that compliment from his father's doppelganger.

"So," Wells cut in, "I get that this has been an important conversation, but maybe we can see about getting everyone home now?"

"We have to do this all the way out here?" Iris looked around the abandoned development in surprise. "I can get that there are some kind of problem with multiple portals, but this seems…"

"When we're dealing with worlds this far away from our own, it's easier to keep our distance to make sure the portals don't… well, get their wires crossed," Wells explained, as Cisco put on his 'Vibe' goggles and raised his hands.

"So you can open these portals this easily?" Pietro looked at the younger scientist in surprise.

"I'm still learning, but it's getting easier," Cisco said, adjusting his stance before he generated a blue glow from his hands. It only took a few seconds before the glow generated another portal, similar to the one in the basement of STAR Labs.

"Just walk through here and that's it?" Bruce asked. "No speed needed?"

"Not any more than the none-speedsters among you would need to just run anywhere in the first place," Cisco confirmed, even as he gritted his teeth while speaking. "So if you could…?"

"Right," Pietro said, pausing to give Barry a final comradely hug before he ran through the portal.

"It has been an honour to assist you in this battle, Barry Allen," Thor said, before following the other speedster.

"Remember," Steve said as he looked at the forensic scientist, "if you ever need us again, just call."

"Glad I inspired you," Bruce said, his brisker tone belying the gratitude in his eyes before he turned and entered the portal just after Steve. For a moment Cisco suddenly winced and staggered back, the portal turning a brief red as opposed to the usual blue, but the moment passed and it returned to normal.

"What was that?" Jessie asked, looking curiously at Cisco as he closed the portal.

"Just… something at the other end; didn't feel like it was anything important," Cisco said, shaking his head slightly as he removed the goggles. "Probably that Bifrost thing Thor mentioned being triggered once he got back; nothing should have happened to anyone at the other end."

"Right," Wells said, looking around the group. "If that's done, maybe we could see about getting the rest of us back to our Earth?"

"No problem," Barry smiled, walking over to place an arm around Caitlin and Cisco to run them back to STAR Labs; Jay could take the Wells', and then they'd come back for Iris, Joe and Wally.

He'd still need time to grieve once their allies from Earth-2 had gone home, and he wasn't going to kid himself that the next few days, weeks, or even months would be easy… but somehow, knowing that Captain America had faith that he could get past this, and seeing how Bruce had learned to cope with his own pain after suffering greater losses at a younger age, Barry had hope that he'd get past what had happened to him as well.

He had lost his father, but he'd gained new allies and friends, and the respect of the mightiest heroes of a whole new Earth; it wasn't the same, but it was going to help.

AN 2: And there we are; the last chapter of this particular crossover, and I hope it meets with your approval.

To answer the most obvious questions; yes, the breach reacting that way when Bruce went through it is meant to reference him being transferred to Sakaar to become the Grandmaster's gladiator, although it's up to you whether that was a natural fluke or deliberate action on the part of the Grandmaster.

On a more immediate note (and one that I'm sure will be more interesting to you all), the approval and support of the Avengers will help inspire Barry to not create 'Flashpoint' in this version of events. Of course, no 'Flashpoint' means no Dominator invasion, which means no initial DC-CW team-up for the Avengers to join, but I won't rule out the possibility of another crossover if I'm so inspired, considering that Barry might still invite the Avengers to his wedding in time to deal with the Earth-X invasion, to say nothing of the possibility of the Avengers asking the Scarlet Speedster for assistance against the Mad Titan…