Youton, or Lava Element, takes the form of melting attacks and defenses. This elemental style has been used by the Yonbi Jinchuuriki Roushi, who developed this style with the help of his Bijuu. It has also been used by Godaime Mizukage through the use of her bloodline limit. Rock kunoichi Kurotsuchi has also used this style. Youton is formed through the simultaneous usage of Fire and Earth styles.
Obsidian is an igneous rock which is highly reflective. It is formed when hot lava material cools so rapidly that atoms are unable to arrange themselves into a crystalline. Obsidian is a naturally occurring volcanic glass formed as an extrusive igneous rock. It is produced when felsic lava extruded from a volcano cools rapidly with minimum crystal growth. Obsidian is commonly found within the margins of rhyolitic lava flows known as obsidian flows, where the chemical composition (high silica content) induces a high viscosity and polymerization degree of the lava.
Who I'd like to meet: Ninjutsu
Nature Transformation
Mei using Lava Release.
Mei is proficient in the nature transformations of Water, Fire, Earth, and Lightning Release. With Water Release, she can create a large torrent that can extinguish a powerful Fire Release technique from Madara Uchiha and quickly use the same water to form a giant dragon. Mei can also use the Hiding in Mist Technique to obscure the movements of herself and her allies. Two years after the Fourth Shinobi World War, her mastery of Water Release enabled her to successfully protect her village from the massive meteorites that had broken off from the falling Moon.
Mei possesses two elemental kekkei genkai, the first of which is Lava Release. By combining earth and fire natures, she can spit out acidic mud that can melt almost anything in its path. The great amount of steam generated after the fluid strikes can serve as an effective smokescreen, allowing her to attack again while the enemy is distracted. A significant amount of exposure was enough to partially melt Madara's Susanoo ribcage. The second kekkei genkai, Boil Release, allows her to simultaneously use water and fire natures to release a corrosive mist that can burn away almost anything it touches. It even managed to burn through Sasuke's Susanoo ribcage. She also has the ability to alter the potency and acidity of the mist created by her Boil Release techniques and is apparently not affected by the mist herself