ash-greninja

An alternate form of Greninja. Similar to Mega Evolution

Key characteristics:

• Red stripes on the face
• Black fins at the sides of the head, resembling Ash's hair
• Body of a lighter shade of blue
• A large water shuriken on its back (Ash-Greninja throws multiple of those shurikens at its foes)
• Often seen with a straight posture and standing on one leg

This tag implicates greninja (learn more).