Breakthroughs and Aether

During one of his monthly check ups with Fury, Percy had SHIELD keep scanning for energy signatures similar to the one Thor put off when he first arrived. In doing so, he hopes that he can forgo the entire plotline of Thor: the dark world movie. Who knows, with what happened with the time stone who knows what kind of ability he may be able to come up with after interacting with it.

<2 months later>

With his cultivation finally breaking through to the peak he can feel the tribulation's call. Afraid to put it off he gives all of his loved ones a call to let them know of the upcoming dangers he will be facing. After a family dinner with his parents and a date with Natasha, he portals himself to Kamar-Taj to give his final heads up.

"Hello Percy I am ever glad you decided to visit me" The Ancient One says with a smile

"I do enjoy our talks, as well as you make the best tea. But that's not what I am here about. I came to ask you for some insurance in case I die doing what I am about to do" Percy says

"The answer is yes. As much as you have done for us, we would be more than gladly to do whatever you need for us" The Ancient Ones replies

"That's a relief. If you do not hear back from me in like a week, take care of my family." Percy says with a smiling before teleporting into the middle of he ocean

Transforming into his draconic form, he triggers his tribulation.

As Natasha emerges from the cavern that Percy and she had been using as their temporary home, she had successfully broken through to foundation establishment. Feeling the sheer power coursing through her, she became excited to show Percy he current power as well as the fact that she is one step closer to being of use to him in combat. Breaking her from her inner thoughts, is a quinnjet landing on their island with a agent of SHIELD alerting her that the energy signatures that Percy had them searching for had been detected. Boarding the quinnjet they head towards their destination to see what is putting off the energy signatures.

Arriving at a bunch of abandoned buildings, Natasha is able to detect something off about the area. Due to her cultivation, she can detect a increase of a strange energy, but is unable to tell exactly what it is. Pushing her senses to the max, she begins to explore the inside of the building. From the upstairs, she can detect that the source of the energy is coming from there. Making her way towards the source she finds nothing a wall and nothing else. Turning around, she begins to walk away in a attempt to block off the area so as to keep any unforeseen accidents from happening with a earth shattering roar is heard causing her to fall backwards before being swallowed up by a invisible spatial tear.

As wave after wave of his lightning tribulation hits him, he approaches the final wave. Preparing himself for the final wave, the lightning transforms itself into a dragon shape before flying at him at speeds he is unable to react to. As the lightning dragon come into contact with his flesh, he can feel his body begin to slowly melt from the sheer heat the lightning. Not willing to let this be the end of him Percy lets out a yell as the energy of the tribulation is absorbed into his body. As the energy absorptions begins to flow into every reach of his body a blinding light is released. As the ball of light becomes brighter and brighter, the size of the light also begins to steadily increase in size as well. As the light ball reaches roughly the size of a small house, a roar that shakes the entire planet is released from the ball as it begins to crack.

As the ball of light slowly begins to crack and fade away, a 5 clawed 250 foot long green dragon is seen slowly flying out of it. (For a good picture of what I'm going for google crimson dragon king but instead of crimson he is a forest green.) Happily flying around in his new form, Percy notices SHIELD aircraft flying towards his direction. Deciding to play a trick on Fury he zooms towards the aircraft before pointing at his mouth, and blowing out of it up into the sky.

Cutting his little prank short before he gets blasted with missiles, not that they would do much to him he hopes, Percy reverts into his human form, also thankfully fully clothed, and boards one of the nearest quinjetts to report his new found power to Fury.