Disclaimer: I do not own Thor, Supergirl or anything else you may recognize

Thank you to everyone who has favorited, followed or reviewed this fic so far.

And at last, we are here with 'Invasion!' I know many people had been looking forward to it, so I hope I deliver. I already did 'Invasion!' once in my very first story- The Devil of Star City.

So I'm not gonna repeat some of the experimental stuff I did there (fighting throughout the city AoU style) but I will do some stuff differently from before at least to make it more interesting.

Some of the stuff here is inspired by Cer1992's 'Alternate Events: When Heroes and Universes Collide' so thank you to him.

Hope everyone enjoys.

Chaos Sorcerer: Thanks for the review. So glad I delivered big time. At least it wasn't as big as in 'Heroes Stand United' where I made you speechless if my memory is right. Glad it was nice work. Who knows, if Thor wasn't around, Clark would probably be 'dead.' Yes, I feel bad for Davis too, though his actions in the finale reduced my sympathy. Thanks for pointing out on Bart. Agreed on Team Flash. Yes, there will be thunder. I will make some changes but it will be interesting still. Yes, Kara's mood will be not as good. Yes Thor will. Doomsday is buried miles under Earth under mazes of tunnels, so it will take many, many years to find a way out. Though if he does, imagine they threw him into the sun where he overcharged for a bit before exploding due to too much power. You will see who crosses over with them. Earth-1 Asgardians might not work though. Sorry. Yes, it is the OP Earth. Thor, Smallville Superman, Beta Ray Bill and Bart. A.C. too. Once you add Kara, it isn't even funny. One of them alone can solo honestly. Can you explain the one with Zeus and Vesuvius? I don't think I remember that. Thank you. Yes, that's where Clark is. Oh yes, while Smallville Jimmy had annoying moments in Seasons 7 and 8, his death was still sad. Arrowverse James, not a fan of the guy. Yes, RIP Astra. I think I've found someone else for Oliver to mouth off on, and be mouthed off on in return. Yes, some parts will be fixed. Thanks a lot for the good luck. And I watched some videos of 'Foil Arms and Hog.' The 'Santa' one, all the three you recommended and 'US Immigration.' This channel deserves much more attention than its getting. It is amazing and actually funny, unlike most other channels these days. Enjoy.

Chapter 13- Welcome to Earth-1

It had been a month since the tragic incident with Davis Bloome aka Doomsday. But a month had not been enough to heal the mental scars anyone carried from the entire ordeal.

Kara, while not shut off, wasn't as bright and cheery as normal, and as Supergirl, had even lost control at times, breaking bones of some criminals and earning criticism from the media for that.

Thor now frequented Asgard more than before to check on Clark, even though he hadn't shown a lot of improvement the entire time he had been there. Frigga had told him that Clark would heal in time but Thor wished he could somehow speed up the process. He travelled to Metropolis at times to keep it safe in Superman's absence. He had taken down one recurring enemy of Superman known as the Prankster.

Lois had returned to Metropolis and was rather shut off now, though she did keep in touch, but she wasn't herself nowadays, for good reason.

J'onn and Alex continued working for the DEO, but it was obvious that they too were deeply affected by everything that had happened.

Lucy had left as she couldn't bear to stay in National City after James' death.

Winn, while deeply in pain himself, was concerned about Kara and Thor too considering how much they had gone through in this situation, especially Kara.

Oliver, Bart, Dinah, Victor, A.C. and Chloe had left to once again carry out their missions around the world. They wished they could do something but it was obvious that they couldn't, unfortunately.

Kara opened the door to her apartment to see Thor sitting with Beta Ray Bill and Oliver. Thor and Bill were both in their armors, their hammers on the ground.

"Bill!" Kara greeted, shocked he was here as he turned to her while she put the packets of groceries she had bought down. "Ollie!"

"Kara", Bill simply said as he nodded at her and she nodded back. "I came to visit."

"So did I", Oliver shrugged as he looked at her.

"Thank you", Kara said simply, not sure what else she could say. Though she knew that she was thankful to them for for the gesture.

"So how fares the search for a new home?" Thor asked him.

"It has hit a dead end for now", Bill said and Thor nodded in sympathy. "But it is still better than being chased by Ymir and his everlasting winter."

"Oh yes, that jackass was creepy", Oliver remembered and shuddered. "Good thing any of us didn't have to face cold creepos like that while we were away."

That was when a blue portal opened in the middle of the room, startling them all. Thor and Bill summoned their hammers to him while Oliver took a fighting stance.

Out of the portal jumped Barry and a shorter Latino man with long hair and glasses.

"Barry?" Kara called out in a mixture of confusion and joy. Last time he was here, he had made the entire atmosphere optimistic.

"Hey", Barry greeted her before turning to Thor. "Hi."

"Good to see you again, Barry Allen", Thor said, gesturing Bill to lower his weapon and Oliver to relax. "Barry Allen is a friend and brave warrior."

"Allen?" Oliver wondered. "You Bart Allen's doppelganger with a different name and face or something?"

"I did hear of Bart last time I was here so I'd say I am", Barry shrugged.

"Well met, Barry Allen. I am Beta Ray Bill", Bill introduced himself as both Barry and the other man looked at him a little awkwardly.

"Hello", Barry said as he held out his hand and Bill shook it while the other man waved to him and he nodded.

He then turned to Thor with excitement on his face and said. "So you are Thor? As in the God of Thunder?"

"Aye", Thor said and the man let out a girly scream of excitement.

"I can't believe it! I am meeting a God!" The man said as he held out his hand and Thor shook it, but he ended up shaking it too long.

"Am I shaking your hand too long?" He asked.

"Yes", Thor said and he let it go.

"Sorry", he blushed.

Barry introduced his friend finally. "This is my friend, Cisco."

"Well, friend is a loose term", Cisco shrugged. "We work together."

Thor, Kara, Bill and Oliver could immediately sense that there was some unspoken tension between the two.

"Hi. Cisco", he said as he shook Kara's hand and then looked around at the room. "I have to say it this is a nice universe you got here."

"Thank you", Kara smiled, feeling flattered.

"I am Oliver Queen", Oliver said as he held out his hand and both Barry and Cisco gasped before the former shook his hand.

"You're Oliver?" Barry asked. This guy's smile was too friendly for Oliver Queen.

"Yeah! I guess I look different on your Earth", Oliver said. "Like you and Bart here look different."

"Well, he is very different in nature too", Cisco said as he and Oliver shook hands. "But we're here for a reason."

"I figured you wouldn't jump over here for a social call", Oliver said.

Barry then looked at them and asked. "Okay, do you remember all those months ago when I helped you out and you promised to do the same for me?"

Kara's face immediately turned serious as she asked. "What are we up against?"

Earth-1

"Team Arrow is here", Felicity Smoak was saying as she gestured to said team. "Team Legends is here. I think that's everyone."

"Nate and Amaya are watching the Waverider", Sara Lance informed her. "The newbies."

A breach opened and Barry and Cisco walked out with Thor, Kara, Beta Ray Bill and Oliver, now in his Green Arrow suit.

"That was so cool", Kara said in a rather excited tone as Thor smiled. It had been a while since she had sounded like this.

"Tell me about it, sis", Oliver shrugged.

"Barry!" A blonde man with a short beard called out to him. "Care to introduce us to your alien friends?"

"Oh yes", Barry said as he gestured to Kara first. "Everyone, this is Kara Danvers, or as she is known on her Earth- Supergirl!"

"What makes her so super?" A dark-skinned young man asked.

"Oh you have no idea my friend", Thor told him as Kara flew into the air and fired Heat Vision at the ground, forming the symbol on her chest.

"I'm convinced", another dark-skinned man next to the blonde one said rather lamely as he looked up at her in awe, along with everyone else as she smiled.

Barry then gestured to Thor. "And this is Donald Blake, who is actually Thor in disguise."

"Wait what?" The blonde man asked as all did a double take on him. "Thor?"

"As in the Norse God of Thunder?" An old man with glasses asked as all stared at him in even more awe than they did Kara.

"I am Thor the Thunderer, Son of Odin, Prince of Asgard", Thor introduced himself, raising Mjolnir into the air as he did so while thunder was heard rumbling in the sky and the Earth shook a little, making everyone's jaws drop even more as they were a little unnerved due to realizing they were standing in the presence of a literal God.

"Your hair….." Felicity said lamely as she gestured to her own. "I thought they'd be….you know…red."

"Oh yeah, that", Thor said. "My brother played a prank on me."

"You mean Loki?" A young woman with shoulder length dark hair next to the blonde man asked Thor.

"Yes, Loki", Thor said and then sighed.

"I wonder if they exist on this Earth", Cisco said.

"Maybe. Maybe not", a tall man with a slightly silly smile said as he regarded them all. Thor, Kara and Oliver noted that his face resembled Clark's to an extent.

"And this", Barry said as he pointed to Beta Ray Bill. "Is Beta Ray Bill, a friend of theirs who also possesses the power of Thor."

"I am Beta Ray Bill of Korban. Well met, residents of this Earth", Bill said with a bow, which everyone returned awkwardly.

"That's it man", the dark-skinned man next to the blonde one said. "I'm out. I'm out of here. Don't contact me."

All laughed at his expense as Barry said to Thor and Kara. "Oh don't worry about him. You should have seen him when he first saw me use super speed."

Barry then mimicked what the man had looked like then and everyone laughed even more as the man lowered his head in embarrassment.

"And this is Oliver Queen of Earth-38, also known as the Green Arrow", Barry said as he gestured to Oliver-38.

Everyone looked at him and their jaws dropped in disbelief.

"You're joking, right?" The woman with the dark shoulder-length hair asked.

"Barry, this is no time for jokes!" The blonde man said sternly. "Besides, it is not amusing."

"I am not joking!" Barry said. "Trust me, he is Oliver Queen, even if he doesn't look like the one we know, but he is."

"I believe you", Felicity said as she raised her hand.

"Oh yes, I am Oliver Queen", Oliver-38 said before quipping. "Unless, you know, the parents I knew abducted me from my real ones and changed my name. In that case, I'm not Oliver Queen."

Everyone laughed nervously as the dark-skinned man next to the blonde one asked. "You're joking, right?"

"Of course I am!" Oliver-38 said and laughed himself.

"Now that we have introduced ourselves, I think it is time for you to return the favor", Thor said as he looked at all the heroes of Earth-1.

"Well, this is Oliver Queen", Barry said as he gestured to the blonde man.

"Wait what?" Oliver-38 asked as he, Kara and Thor did a double take on him.

"What?" Oliver-1 asked.

"Man, when I first heard my doppelganger on here was different from me in looks AND personality, I figured he was even more mellow. I didn't look as serious as you on my worst days", Oliver-38 said to him, giving him an incredulous look.

Oliver-1 said to him. "The only reason I'm even willing to trust you and your friends is because Barry vouches for you guys."

"Oh I don't trust you either. I would have my wife slap me if my head ends up that far in my ass", Oliver-38 countered.

"Okay, guys, I think that is enough for now", Barry said as he stepped between them. "We have important matters to take care of. You can shoot at each other later."

"This day got so much weirder", the dark-skin man muttered to himself.

"And you would be?" Thor asked him.

"John Diggle. Spartan", he introduced himself.

"I don't understand", Thor said as he looked at him. "You don't look like a Spartan to me. Are you their descendant or-"

"It's my codename", Dig said.

"Oh!" Thor nodded as all chuckled a bit at the 'fish out of water' comedy he had unintentionally supplied.

"You can call me Dig", he said before looking at them. "Got to say, wasn't expecting to meet aliens today. And another Oliver Queen."

"Me neither on the second one", the woman with shoulder length dark hair said. "Thea Queen. Ollie's sister. Codename is Speedy."

"So you've a sister?" Oliver-38 asked Oliver-1 who simply nodded. "I'm an only child."

Kara then turned to the Legends. "You all are?"

"Sara Lance, White Canary", Sara introduced herself.

"Lance?" Oliver-38 asked as he shared looks with Thor and Kara.

"Are you related to Dinah Lance?" Kara asked her.

"She is my teammate and is called Black Canary", Oliver-38 supplied.

"I do", Sara said with a sad sigh. "Dinah Lance is mom's name, and my sister's name was Dinah Laurel Lance. She was Black Canary for a while until a deranged magic-wielding psychopath killed her months ago."

"Dinah's dead?" Oliver-38 asked in disbelief.

"Yes", Oliver-1 said in a pained voice as both he and Sara looked saddened.

"I'm sorry", Kara and Thor said simultaneously, both knowing the pain of losing siblings in different ways.

"My condolences", Bill said respectfully with closed eyes.

"I'm really sorry", Oliver-38 said too, saddened to know that another version of his close friend was dead.

"Don't be. The one who killed her on the other hand-" Sara trailed off with a murderous expression.

Bill then asked the old man and his dark-skinned companion. "You are?"

"Professor Martin Stein", the old man introduced himself.

"Jefferson Jackson", the younger dark-skinned man said. "We fuse into one superhero called Firestorm."

"I don't think even I have seen that before", Thor shrugged.

Kara then asked the man with the sweet and silly smile who seemed to resemble Clark to an extent. "And you?"

"Ray Palmer. The Atom", Ray said as he raised his hand and smiled.

"And that leaves you", Thor said to the last man as he looked up from the burrito he was eating.

"Hmmm? Heat Wave", he said in a barely interested voice.

"Who might you be?" Oliver-38 then asked Felicity.

"Felicity Smoak. Codename Overwatch. Part of Team Arrow", she introduced herself excitedly.

"Tech genius?" Kara asked and she nodded.

"Right", Oliver-38 said, reminded of Chloe, who was like this Felicity, but wasn't this fast-paced at talking anymore due to having grown more mature, which he didn't see in Felicity, not that it bothered him.

"That leaves the two of you", Thor said as he pointed at the red-haired woman and the dark-skinned one.

"I am Caitlin Snow, doctor in Team Flash", Caitlin introduced herself politely with a smile.

"Iris West", Iris simply introduced herself.

"Well, that concludes introductions", Bill said and all nodded.

"Barry, so, Oliver Queen is the Green Arrow?" Thor heard Iris West ask Barry in a hushed tone.

"Yeah", Barry nodded.

"Oh, my God. He just got so much hotter", she said, gushing over him.

"Oh, my God", Barry sighed.

Thor shared a look with Kara and Oliver, who both also had the same look as him. Iris clearly wasn't someone they were going to get along with considering the way she was making Barry uncomfortable on purpose.

"Maybe we should get started", Oliver-1 said.

"Before we get started, how are we gonna address the two different Olivers?" Ray asked. "It would get confusing real soon if we call them both 'Oliver.'"

"You're right", Barry agreed as he looked to them both. "Maybe one of you can be 'Oliver' while the other will be 'Ollie.'"

"I'll be Oliver. He will be Ollie", Oliver-1 said firmly as he glanced at Oliver-38.

"Fine by me", Ollie shrugged.

"Well then, let's get started", Barry said, gesturing to Cisco.

Cisco nodded and showed them something on a screen. It did not look like a human. It seemed like some kind of zombie.

"These are the Dominators", Barry said. "We do not know much about them but they're not friendly and they are not here for peace."

"And they're strong and dangerous", Kara said seriously as everyone looked at her. "I heard a lot about them when I was younger. They came to my planet before I was born, experimented on my people, killed a lot more."

"Oh I remember killing them all long ago when I was younger", Thor said as all turned to him with incredulous looks.

"All?" Barry asked, sure he had misheard. "When you were younger? Like how much?"

"Midgardians would call it 'teenager'", Thor said and all gasped.

"So you killed all the Dominators as a teenager?" Kara asked incredulously, not having known that.

"Well, he is a powerful warrior, I don't know why you are all so surprised", Bill said, not knowing the reason why everyone was so shocked.

"So you were what, the Asgardian equivalent of a bullheaded teenager or something?" Ollie asked with raised eyebrows.

"Fair comparison", Thor shrugged.

"He puts me to shame for sure", Oliver muttered.

"Me too", Ollie said.

"Even me", Thea added before looking at the three. "But from what I hear, they are not the only strong ones. Barry here tells us the three of you are more powerful than locomotives."

"I have my strength as long as I have access to a yellow sun", Kara told them. "It's where my powers come from."

"Not the case with me", Thor said.

"Or me", Bill added.

"I think we should use them all as stand-ins for training", Oliver said.

"Are you serious?" Ollie asked him incredulously.

"Yes", Oliver said.

"Do you know what they can do? You won't stand a 0.1% chance in hell against one of 'em, let against all", Ollie said.

"Alien invasions shouldn't be taken lightly", Oliver said to him. "If you take your responsibility as seriously as I do, you'd understand."

"Well, now I do understand why I'm not this serious. And I'm glad I am not", Ollie said as all noticed how different they both were. Oliver and Thea were both reminded of how the former used to be before Lian Yu by Ollie.

"Being like this keeps me alive", Oliver said. "My point stands."

"Since when is Robin Hood calling the shots?" Mick asked.

"What I think Mick is trying to say is that it would be nice to know who is in-charge around here", Jax interjected before things could escalate.

"He's right", Ray said. "Maybe we should take a vote. Someone we can all trust."

"Like an election but smaller", Thor said and Ray nodded. "Smart."

"I think Thor should do it", Bill said as Thor looked at him gratefully. "He is a great warrior and leader of forces."

"What he said", Kara said as she pointed at Bill. "Though Ollie will be good too. He leads the Justice League after all."

"Thanks for the vote of confidence", Ollie said.

"I appreciate it, but the residents of this Earth number more than us, so their leader should be someone they know well and trust", Thor said and the three nodded, knowing he had a point.

"Well my vote goes to Oliver", Cisco said without looking at Barry. "I trust him."

Everyone could sense the tension between Barry and Cisco.

"Thank you for the vote of confidence, Cisco", Oliver said. "But Barry brought us all together. I think it should be him."

"Fair enough", Cisco said though it was obvious he had an issue with it.

"I think you can do it", Thor agreed as he nodded to Barry who smiled gratefully.

"Well", Barry said. "As team leader I think we should start out by..." he stopped as he realized he didn't know what to do.

"Doing a test run", Oliver supplied helpfully in a slightly annoyed tone.

"Doing a test run", Barry said even though he wasn't sure what that was. "A test run."

"Against the three of us", Thor supplied this time as he pointed to himself, Kara and Bill.

"Against the three of them", Barry repeated what he had heard. "A test run against the three of them."

"Are we just supposed to pretend like we don't hear them?" Sara asked with an amused smirk as she pointed at Thor and Oliver while everyone chuckled.

"Okay everyone", Barry said. "Suit up. Look alive", Sara gave an amused smirk while Thor and Oliver nodded. "We're training to fight aliens by fighting Gods and aliens."

"It would be futile on your part but it will be helpful in teaching you what not to do", Thor said as everyone had a bad feeling now. They were really gonna regret trying to spar with the three of them.

Everyone then started getting ready for training. Or beatdown from another point of view.

So hope it's a good start here.

I brought in Beta Ray Bill as well as I have a plan for him.

Originally, I was only going to bring him with Thor and Kara but Arrowverse Oliver not meeting Smallville Oliver would be a missed opportunity and I was inspired to do so by Cer1992's fic.

The interactions between Oliver and Ollie are taken/inspired from his fic so thank you to him.

Hope everyone enjoyed and see you all next time with another chapter.