There might also be antagonists in the fanfiction. They could be jealous of May's new - found power from her transformation or want to use it for their own evil purposes. These antagonists could be other trainers or even organizations. They would constantly try to either capture May in her transformed state or find a way to take away her transformation ability, creating a lot of conflict and action in the story.
In Pokemon may transformation fanfiction, a common concept is the transformation being tied to emotions or a special power source. May could transform when she reaches a certain level of excitement or when she discovers a hidden power within herself. This can lead to her having to learn how to control her transformations, and there could be some comical or intense moments as she tries to keep her new form a secret from her friends at first.
A strange and rare item could be the cause. Maybe a Vulpix stumbles upon an ancient amulet that has the power to transform Pokemon. Once the Vulpix touches it, the transformation occurs. This amulet could have been lost for centuries and have some sort of legend associated with it.
When Celebi initiates the transformation, it's like a wave of emerald light washes over the target. First, there's a tingling sensation all over the body. Then, the physical features begin to shift. If it's a transformation into a flying - type Pokemon, the back might start to bulge as wings start to form, feathers sprouting out in a flurry. The face would change too, the nose becoming a beak perhaps, and the eyes taking on a different shape and color. Every detail of the transformation can be described in a very tactile way, making the reader feel as if they are witnessing it firsthand. You can also add in the sounds, like a soft whooshing as the transformation energy moves around.
A possible fanfiction plot could be that Ash, Serena, and May are invited to a mysterious island full of unknown Pokemon. They have to work together to survive and discover the secrets of the island. Ash's leadership, Serena's ability to communicate with Pokemon, and May's quick decision - making skills would be crucial.
Well, it's completely inappropriate. Pokémon has always been about positive values like friendship, adventure, and growth. Creating fanfiction with such inappropriate themes as 'naked pokemon' not only distorts the original concept but also might be offensive to a large number of fans who enjoy the series for its intended charm and wholesomeness.
In many fanfictions, Ash's shadow Pokémon transformation can be a really cool concept. It might happen due to some dark energy or a special encounter. For example, he could be influenced by a shadowy force while exploring an abandoned Pokémon facility. This transformation could give his Pokémon enhanced, but more aggressive powers.
He could gain the ability to use Pokemon - specific techniques in combat. For instance, he might be able to use Quick Attack, which would make him move at an incredibly fast speed, much like his own speed - based jutsu in Naruto. His opponents would be caught off - guard by these new moves.