Thunderstruck

Chapter 1: The Change

Starts in Season 2 Episode 7

Callum and Rayla snuck down to the edge of the clearing, Ezran had stayed behind to watch Zym. Despite having been bedridden for a while, he was keeping up with Rayla rather easily.
They split up, with Callum intending to be bait while Rayla worked to free the dragon of it's bonds. He grabbed a shield with the intention of taking it somewhere to make a distracting noise, but while carrying the steel shield, he began to feel lightheaded and tripped, dropping the shield, and alerting everyone with a loud clang, at the same time they found Rayla who had cut the last rope holding the dragon down.

"Callum! We were so worried about you!" Claudia said happily, now we can put this all behind us and you can come home, where you should be"

"You get Callum, I'll get the elf" said Soren, raising his broadsword

"I told you, I'm not going back, not yet" Callum said, but from the look in Claudia's eyes, he wouldn't be able to convince her

"Don't kill her Soren, she can lead us to Ezran and the baby dragon" Claudia said "and then all this can finally be over"

Two soldiers held Callum in place, while Claudia turned her attention to Rayla, and started to prepare a dark spell, using what looked like an elf horn as an ingredient.

"Gninthgil Krad Htrof Emoc!" her voice distorted as she recited the incantation and her arm was wreathed in black lightning, that she intended to use on Rayla.

Callum saw this in slow motion and then without thinking, he broke free of the soldiers, who had become mesmerized by the display, and then he did something he never thought he would do in his life. He grabbed Claudia by the arm wreathed in Black Lightning and redirected it to strike the wood stakes holding the chains in place and blew them out of the ground, but in the process, he took a lot of the lightning into himself. He fell to the floor in pain keeping his mouth shut while Pyrrha lashed her tail at the soldiers. When Soren tried to attack with his sword, he was swatted away by the beast's tale into a tree, winding him.

Callum was still on the floor when the soldiers decided it was not worth it and ran with Claudia grabbing Soren and carrying him away while he struggles against the magic forcing him to follow her as they fled.

When they left Rayla ran up to Callum who was writhing in agony and saw what was happening he had teal blue scales like Zym's, he was slowly growing larger causing his clothing to tighten as he grew. Rayla and Ezran carried him back to the wagon with him helping as much as he could. His hair was migrating to his neck as they went, and he knew that in a matter of seconds the scales will cover his whole face and body with how fast he feels them forming on him. He feels an explosion of pain on his back as well as lower spine as his wings and tail burst out of him with his clothes exploding as well. He lets out a silent screech of pain as he falls into unconsciousness. As he slept his form changed into one of a young Storm Dragon that they struggled to hide fully in the cart. Once he was in no obvious pain Ezran cautiously moved over and tried to wake Callum to no success which caused him to get more anxious, Rayla also came over and checked whether he was alive and released a sigh of relief when she felt a pulse. Rayla then went to the front of the cart to get going because they didn't want the soldiers finding them when they got back.