Legendary 7

Legendary 7 is a sequel to Emerald of Evil and a spinoff that focuses on Kuroninja's 7 girlfriends. It also features the return of Akuroninja and his Enforcers, while also introducing Metalization. It also features the Legendary 7 Armour of Kuroninja.

The full story can be read here.

Summary
Kuroninja gets captured so Umika forms a team to rescue him.

Enforcers

 * Tyranno Troopers
 * Mammoth Troopers
 * Ptera Troopers
 * Tiger Troopers

Yodonheim

 * Rugby Jamen
 * Bechats

Umika Hayami/Lupin Yellow

 * Haruka Kudo

Anti-Kuroninja

 * Masaki Sato, Sakura Oda

Akuroninja

 * Riho Sayashi (metal)

Trivia

 * This is one of the few times since January 2019 that Kuroninja didn't use the Blade of Kings in an episode.
 * The story takes place during and after episode 2 of Mashin Sentai Kiramager.
 * If you take the first letter from the title of each chapter, it spells out "Aoi Rena."