Mitoshi absorbs water as part of her power

(Family Reunion, Chapter 3)

Soon, the trio landed at a large lake nearby Route 35. Antoshi promptly pulled out Fireball's Poké Ball to let him out.

“This is where you wanted to take us?” Antoshi mused, both he and Fireball looking around at the picturesque scenery.

“Indeed it is,” Serenity replied. “Mitoshi, why don't you take a dip in the water and see what happens?”

“Oh, … all right,” Mitoshi replied.

She waded her bare, watery feet along the shore of the lake, inadvertently scaring off a handful of slow-moving Magikarp under the surface. The massive hole in her body began to fill itself back up from the body of water. Fireball and the two siblings looked on in amazement.

“Now,” Serenity said, “try to return yourself to normal.”

Mitoshi focused for a moment. Her skin and clothing slowly became visible, the water appearing to recede back into her body.