Labyrinth and Magic Gunner

 is the fourth episode of the Trinity Seven series, initially broadcasted on October 14, 2014 in TV Tokyo.

Crunchyroll
A power leaks from underneath the school, Arata and the gang head down into the labyrinth to protect the school from the collapse phenomenon.

Summary
Another Breakdown Phenomenon happens again in the academy, as shown by people with low magical capabilities falling asleep due to the disturbance. Lilith, Arata, Levi, and the Grimoire Security go to see Master Biblia to figure out the source. It's learned that the cause of the Breakdown Phenomenon is Yui, a member of the Trinity Seven, losing control of her magic. After that, Lilith, Arata and Levy try to catch up with the Grimoire Security as they go to the source of Breakdown Phenomenon, in the academy's dungeon. After Arata, Arin, Lilith and Levi go through the dungeon, they run into Mira and Akio and stop them from advancing. To buy time, Levi challenges Akio to a one-on-one fight, while Arata, Arin and Lilith go on ahead to Yui's room. Arata's magic resonate with the magic of the code D monster found in the room and falls down to his feet. When the Grimoire Security arrived, Lilith and Arin together with the Grimoire Security proceeds on to fight the monster. After having a conversation with Levi, Arata is able to properly use the magic that he copied from Lilith to successfully stop the Breakdown Phenomenon caused by Yui. After waking up, Yui immediately hugs Arata and repeatedly shows her affection to him.

Characters

 * Arata Kasuga
 * Sora as Grimoire form
 * Lilith Asami
 * Levi Kazama
 * Arin Kannazuki

Returning Characters

 * Akio Fudo
 * Mira Yamana
 * Master Biblia
 * Yui Kurata

Cameo Appearance

 * Selina Sherlock

Trivia
TBA