In the Legend flashback, Sae and company are still being chase only this time by large mutant dogs. The 17 Platoon takes a day off from training with Nina and Harley watching the inter-platoon matches while Layfon goes out with Mei-Shen for lunch. However, the city of Zuellni falls into a ditch, attracting a large number of Larvae-Stage Filth monsters from their nest below ground. With an invasion into the Regios eminent, Karian orders all Military Arts Students to defend the city and repel the monsters despite most of them having no experience fighting against Filth monsters. As Nina leads Sharnid and the 9th Platoon to defend the North-West section of the city, Layfon asks her to evacuate since they are no match against the bugs but she refuse and ask him why won't he fight.
True to his words, Nina and 4th Platoon's weapons barely makes a scratch against them and by night time, the 4th Platoons abandon Nina and Sharnid as more bugs appear. When one of them is about to kill Nina, she is save by Layfon (who now fights to protect his friends) with a modified kei powered whip sword dite based on the weapon of Lintesce of the Heavens Blade. With his new dite, Layfon easily kills hundreds of Filth monster and with the help of Felli's power, locates the Queen Filth monster nest outside of the city and kill it. As sunrise appears and most of the bugs now "immobile" to the death of the queen, Layfon returns and collapses into Nina chest from exhaustion whom latter can only do but congratulate him.
未だに連携の取れない17小隊に苛立つニーナ。一方レイフォンも、過去の出来事を引きずったまま、悩む日々を送っていた。そんな中、ツェルニの脚が汚染獣の巣穴へと踏み込んでしまう。無数に襲い掛かる、汚染獣の幼生態。そして、幼生態の背後には凶悪な母体が!!初めての汚染獣襲撃にパニックになったツェルニをレイフォンが駆ける!!
