Ninjitsu Nemeses

Ninjitsu Nemeses is a Hardmode event that can occur any night. It is basically a ninja invasion. It cannot be summoned, although it generally has a higher chance to spawn before the Mechanical Bosses. It is constructed of 5 waves.

Mobs

 * Kunoichi (All waves) Sprints at player and throws Master Shurikens rapidly
 * Master Taijitsu (All waves) Kicks at the player when close enough
 * Yin (Waves 2+) Stands in place and rapidly throws Yins that home in with high speed, occasionally teleporting toward the player
 * Yang (Waves 3+) Stands in place and rapidly throws Yangs that go through blocks and deal high damage, moving even faster than Laser Rifles
 * Master Katana (Waves 4+) Runs at the player and swings a Master Blade when close enough
 * Samurai (Miniboss) (Any wave) Lumbers towards the player and eventually shooting Bamboo Arrows and throwing Master Knives
 * Master Nunchaku (Wave 5) Sprints at the player and swinging nunchaku
 * Black Belt (Wave 5) Attacks by kicking, throwing yin-yangs, swinging a Master Blade, swinging nunchaku, and finally
 * Master Yinyang (Wave 5) Throws yins, yangs, and yin-yangs, which separate via explosion on contact, leaving a yin and a yang that propel themselves at the player.
 * Marquis (Boss) (Wave 5) Throws Kuni at the player and at half health slashes with a Master Blade, at 1/3 health emanates Japanese words (such as 力, 電源, or その) that spin towards the player exactly like a Demon Scythe; has the ability to vanish and reappear elsewhere when taking too much damage