Henry kept his hand closed tight around the sword as he looked at David fighting Adda. His grandfather had managed to keep Adda away from him, by making himself the target, but that fight was clearly taking his energy away. When their Adda raised his sword, ready to try and cut David's head open, Henry burst in, pushed his grandfather to the side and raised his sword above his head, making Adda's hit it. With most of his body unprotected, Henry kick Adda in the knee, and when he bended a little, Henry cut his thigh. Right before he took a few steps back, Henry kick Adda again right above the cut he had just opened, making Adda stop laughing for a bit and scream in pain. Henry turned to David for a second and smiled at him, as David watched, clearly impressed.
It was when Henry turn back to Adda and his wound, which was already starting to heal, that he began having some flashbacks to when Henry hurt Adda for the first time. And as he saw that scene again, he got to the conclusion that was the first time, not just him, but anyone else had ever hurt Adda. Seriously injured him. The only time someone made him bleed. And if he bled, then he could be killed. And then he realized that maybe it wasn't just a simply enchanted sword which hurt Adda to that point: it was the fact the sword was wheeled by him. And the reason why it didn't kill him on the spot, was because an enchanted sword was the wrong weapon. And Henry knew exactly which was the right one. He had no idea how he knew that, but inside him he was sure that was truth.
He turned back to the real Adda and watched him as he was kneeling on the ground, still laughing. If he was down, that probably meant they were weakening him, but Henry also knew they were weakening themselves much faster, and they wouldn't be able to hold him down until he died. At least not if he didn't help.
Henry started walking to the little circle they had formed, ignoring his grandfather's calls, and stopped when he got close to Regina. He looked straight at Adda as Adda stared back at him with an empty look. Henry couldn't see Adda's version of happiness in those eyes, which could mean he was trying to hide whatever he was feeling. Could that be fear? Maybe.
Adda knew from the start not a lot of things could kill him, but he also always knew there was possibly something which could, or rather someone. Someone so powerful that he could change anything he wanted just by writing a few words. But Adda also knew Henry wasn't just special because he was the Author. In fact, even though not a lot of people knew about this, Henry was the most powerful author who had ever lived, because he had one thing none of the previous ones did: Belief. And not just any belief, but the Truest. And he knew that combined, created a powerful weapon.
Looking back at Henry while he was on the ground made Adda realize that he knew everything. He didn't know how, and he surely didn't care, but it was clear Henry knew what he and only he could do. Not as hardly as the heroes might have hoped, Adda got up from the floor and created a shield around himself, one which immediately started to be taken down. But before it did, he manage to create a blast so powerful that made everyone around him fly away. To be honest with himself, not even Adda knew he could do that at that point, but he had to ty it. When he opened his eyes again, he realized all his doppelgangers had returned to his body. But that didn't matter. Not anymore.
He turned to Henry, raised his arm in his direction and lift him in the air, chocking him. "You think you're so smart, boy? How about you find out what true power looks like?"
Everyone looked shocked as Henry reached for his neck in an instinctive attempt to get every little piece of air he could find, to just take one more breath. But it was in vain. He looked at Adda panicked, as he saw his determined face looking back at him. In that moment, Henry was sure what Adda wanted more than anything in the world, was to drop his lifeless body on the floor.
After losing her consciousness for a few seconds, Regina opened her eyes and looked around, making her feel even more dizzy than she already was. She closed her eyes again, rubbed her head and she was better a few seconds later. Not the best, but better. And when she looked back up, she immediately saw her son right in front of Adda and with his feet flying in the ground as he made chocking sounds, trying to catch a breath. Regina didn't need any more motivation to forget the pain and get up, but when she did, she was blasted away again. Adda didn't even bother to turn his eyes away from Henry, but he reached his other arm in her direction.
Right after, he created a shield around Henry and himself, making sure no one was able to interfere. He was definitely gonna enjoy that. And when he killed Henry, he would kill everyone else, one by one, so the others could watch and realize they were next. And then he would get what he wanted all along. "You should mess with people your own size, kid. This is what happens when you try to play big boy without having what it takes to move finish your plan."
Henry continued to rub his throat in despair, trying to, not even say something, or do something, but just to breathe. To breathe at least once so he'd survive for a few more seconds. Because that was how bad it was getting already: finding out a way to continue surviving for one more second. But nothing happened other then the lack of air starting to be felt more in more. His mouth opened trying to catch just a glimpse of it, but with no luck whatsoever.
Regina tried to make a run for them again, tried to use her magic to break the shield. As everyone recovered from Adda's blast, they all started helping Regina, but they were just too weakened and Adda was still too powerful. But Regina would sure as hell not give up. And she didn't. At least for a few more seconds. But when she saw Adda drop Henry's dead body to the floor, she knew it was over. She fell to the ground as she felt all her energies leaving her body. She cuddled to a little ball as her entire soul shatter with the sound of Henry's body hitting the ground. Her son. The little boy she raised, the one recently turned to a man, right in front of her with his dead eyes staring back at her and with his mouth still open, like he still hoped to get some air. But all hope was lost.
Henry continued with his mouth wide open in a pointless effort to catch some air. Or maybe not so pointless after all, because suddenly something changed inside him. While his mouth continued opened, gasping for air, a little bit of it entered, down his throat and to his lounges. And after that one, another came, and another. Out of nowhere, Henry started to breathe again. He could feel his throat was still blocked, but it was like a little bit of the door Adda had closed, opened. And Henry knew he had to use that against Adda. And he knew just how to do it.
He kept looking at their enemy with the best look of despair he could make, he kept his mouth open, his hands on his neck, as he hoped to breathe indistinctively. And it seemed to have worked, because a couple minutes later, Adda dropped Henry's body on the ground. Henry was heartbroken when he found himself looking at his mother, who was crying her eyes out, thinking he was dead. As much as it pained him to see that, Henry knew he couldn't say or do anything until the moment was right. He needed to catch Adda off guard. Henry waited patiently, trying his best not to move, as he saw Adda turn to the others. Henry couldn't see his face, but he sure as hell could bet what was left of his life that Adda was showing the biggest smile he ever experienced. "So, who's next?"
Henry kept waiting as Adda opened the shield, putting Regina inside it, and started walking to her. "How about you! Do you want to join your son?" It was a good thing Henry had to stay quiet, because he was speechless watching Regina not even fight back. As he almost saw a little bit of happiness in her eyes when Adda offered himself to kill her. Henry knew he had to do something before the situation got even worse.
Moving his hand slowly, Henry started reaching for his pocket, doing only the movements which were really required, not wanting to call any attention to himself, and grabbed his pen. He had it with him at all times, and that once was no different. In the exact opposite of before, Henry got up as quickly as he could, and ran to Adda. "Don't you dare hurt my mom!" Henry regretted speaking the second he opened his mouth, but then it was already too late. Before he was able to reach Adda, Henry watched him turn around and stare at him. The only thing which saved the moment was the fact that Adda was so shocked Henry was alive, he couldn't think of what to do for one second. And that was more than enough time for Henry to get to him, and stab Adda with his pen close to his heart.
When Adda fell on his knees, the shield was immediately down, as Henry ran to Regina, hugging her like she was the last person on Earth. Regina didn't even know what was going on, nor how any of that was possible, but all she cared about in that moment was the fact that Henry was alive and right there with her. She hugged her son (more like squeezed him in her arms), as the tears of pure heartbreak turned to pure happiness.
Seeing Adda weak on the ground, and with lots of blood start to come out from his wound, Rumple knew that was the chance they needed to take him down for good. Even though he was already weakened, Rumple pulled one last effort and started blasting him with magic again. After him, everyone joined, making the circle around him hole again. Even Regina joined after a few seconds.
In an effort to help, Snow and Robin started shooting their enchanted arrows at Adda, and everyone else who had no magic started throwing their swords at him. None of them knew if that would actually help, but what they did know was that they couldn't stand there and do nothing.
After this, it didn't take long for Adda to start screaming as the pain started being too much. With arrows and swords stabbing his body and the blast of the most powerful coven ever created, Adda saw all his plans go to the trash, as he started feeling a huge amount of blackness take over his whole soul. When a huge amount of light appeared, which illuminated Storybrooke's main street more than the sun ever would, every one of the heroes protected their eyes. When the light faded, there was nothing but Henry's pen standing in the middle of the circle.
(PS: Even though this really is the end of Adda, there is still one more chapter coming. The last one. So please, bear with me for a little while longer)