Told from Wendy's point of view
The battle was going poorly she could tell that everybody was already exhausted and she was no different. I tried to keep everybody up and fighting, providing healing spells and power ups, it was not enough. The basilisk like beast was huge and breathed a noxious gas that sapped your energy, each one of its talons were razor sharp and seemed unbreakable. Not to mention the minions it was able to summon out of the ground where just smaller versions of its self. The monster was too much for the five mages and two exceeds to handle.
Then it happened, faster than I should could even scream for her to move. Lucy had been fighting the minions the same as her trying to keep them of the other three as the dealt with the big one. She had her back to the beast. Natsu saw it happen and lunged for her at the last second but he was not fast enough. The beast hit her with its large foot. Natsu was at her side in a moment. I ran as fast as I could hoping desperately there was something I could do. I arrived and it was not looking good there was a gash the ran the length of her abdomen from shoulder to hip.
I heard Natsu whisper one thing to her before standing "I love you" he turned to me In a serious tone that I thought him incapable of, he told me " get her out of here. Run as far as you can" He turned to the other two trying to keep the monster and its minions away "you two to, leave" the temperature was already rising getting to hot to breath I looked up from Lucy to see Natsu. He had entered dragon force his scales forming. It seemed to have taken one step more, he was growing horns. Gray and Erza went to protest when he unleashed a dragon's roar that incinerated five of the minions. The looked at each other and agreed grading Gray made ice gurney rolling the still bleeding but conscious Lucy onto it.
Everyone was running after that trying desperately to escape Natsu's fire. We reached a cliff that over looked the battle filed. I started to work on Lucy holding back the tears as I tried to close the large wound that streaked across her abdomen. She was trying to talk "Natsu, where is Natsu" she coughed out
"He is fine just finishing the fight while we get you better" Erza reassured her I closed the wound stopping the bleeding the best I could I told them we needed to get her back to the guild now. They weren't listening anymore they were watching the battle. Natsu did not look like Natsu. He had his dragon scales, he also had horn coming from the top of his head, his hand were not human they were covered in red scales and his fingers ended in a claw, his eyes where a yellow and where closer to a cats rather than human's. The battle was fierce him jumping around destroying many minions with each blow. Finally he jumped high into the air higher then should be possible even for him.
Erza screamed "Get down" before changing into her guard armor Gray quickly put up and ice make wall and I covered Lucy with my body not taking my eyes from the fight. Natsu hit the head of the monster and the explosion happened. It was brighter than the sun. Then the shock wave hit us. Erza blocked it first taking the majority of it in her shield armor. Gray quickly started to make multiple ice walls the heat so intense that it was melting them. Then it was over the blast had left nothing, but a large hole and many miles of burnt down forest. Natsu landed next to us. He still did not look like Natsu. Erza and Gray stood between us and him unsure what his intentions were. Then it started to flake away. His Scales on his face started to turn back to skin his eyes shifted back to the normal look. The horns and scales on his hands turned to ash blowing away. He stood for a moment before collapsing into Erza.
Erza flew me and Lucy to the guild while Gray sprinted with Natsu on his back. Happy was in tears over both his friends while Carla flew next to me as I still worked to save Lucy. We arrived not long after with Lucy, Erza left immediately to grab Natsu and fly him hear as soon as possible. Porlyusica arrived shortly after starting to work on her internal injuries. She was stabilized after a half-hour of work.
Natsu arrived just then. He had used all his magic and by all rights should not be alive. Porlyusica gave out instructions to get Gajeel and Lexus hoping to infuse their dragon slayer magic to save him. They arrived and she started the transfer. It took an hour to get him from the brink. Lucy awoke three days later as I changed her bandages.
"Wendy, what happened?" she asked me.
"Do you remember the basilisk fight?" she nodded "You got hurt really bad. It will probably scar. You scared us you know Natsu, he lost it after you got hurt I mean really lost it."
"where is he?" she asked I stepped out of the way allowing her to see the bed next to her with the still comatose Natsu bandaged up. I told her in detail about what had happened apparently the blast was visible from the guild. The reports of the shock wave blowing out windows where coming in. "Is he going to be okay?" she asked tears streaming.
"He should be, he lost most of all of his magic and lived we are not sure what will happen. Porlyusica said that has never happened before." She looked at Lucy who was trying desperately to hold back the sobs. "He will be fine its Natsu he will sleep for a few days and be up craving food like always." I reassured her.
I was right the next day he awoke. Though I was wrong about what he craved. I entered the medical room and found him kissing her deeply luckily I saw them and not Porlyusica who quickly went on a rant about how he should be in bed and how much she hated humans. They both got better and soon announced their love Mira was over joyed as was everyone else.