Demonic Illusion: Swallowtail Swarm

This genjutsu has the user transform into a swarm of illusory butterflies, which then converge upon the opponent, blocking their vision and leaving them vulnerable to an attack by the caster. Alternatively, the user can summon a swarm of real butterflies and use this technique to mix in illusory ones, making it harder for an opponent to target a specific butterfly.