So, this story is basically going to somewhat be a different version of the 'Invasion!' crossover event, although most of the plotpoints will be the same. The only major difference will be that Kara has an E1 human doppelganger who was known by Oliver, Thea and Sara. This story was inspired by a post made by danversqueen on IG. Go check her page out for SuperArrow edits. Here is the prologue:

(15 May 2013)

Oliver skidded with his motorbike right in front of the back entrance to CNRI. Somehow, through all of the chaos, he could hear Thea and Laurel's screams in the distance, screaming for Kara. "They aren't in the building", Oliver thought to himself, which was great. They're safe, but Kara was still there. He hopped off his bike and ran inside the building, taking off his helmet once inside.

Immediately, he started scanning the wreckage and debris before him. To his left was a man lying stomach down. He quickly ran up to him and turned him over. Tommy. Oliver pressed his fingers against his throat… he was alive, just unconscious. He heard a slight movement and whipped to his right, spotting the lower half of a woman's body, unable to see her face through the debris.

"I'm here, Oliver".

He heard the faint words and recognized Kara's voice, immediately jumping to remove the blocks of concrete debris from around her.

"You're gonna be fine!"

Those were the only words Oliver could speak up. He didn't know whether he was trying to convince Kara or himself. He looked at her picture every day for 5 years that he was gone, and he had just got her back. There was no way he was going to lose her again. He removed the final piece of rubble from beside her and for the first time got a clear view of her upper body… the metal rod lodged in her chest.

"Kara…"

"Is Thea safe? Thea… Laurel... Tommy and I tried to get them out of here", said Kara, speaking just a little louder than a whisper.

"Yeah, yeah, you did! You saved them", Oliver said, forcing a smile onto his face, "Hey, I'm going to get you out of here, you're going to be fine", continued Oliver, as he started looking at the ground around Kara's body. Surely there was a way to move her, transport her…

"Oliver, stop", whimpered Kara, "I'm sorry"

"No… Don't apologise…"

"I heard Thea was here… I had to come get her, save her… I tried to be a hero… like you, Ollie… but I'm not…"

"No, no, you are. You are better than me… better than I could ever be… and that's why I love you, Kara". Oliver was forcing a smile onto his face and fighting back the urge to let a single tear fall from his eye. He didn't want to believe it, but these were her final moments. He wanted her last image of him to be of him smiling, not crying.

"Never lose that smile, Ollie", she whimpered, keeping tha same radiant smile on her face that never failed to light Oliver's world up.

"I won't"

"It's what I love most about you…" She barely finished her words, before her eyes closed and her head started slumping to the side.

"No, no, stay with me", said Oliver as he caught her head. He couldn't hold back the tears anymore, "It should have been me… Open your eyes Kara! Please, open your eyes…"