Band Together! Quartet

'''Band Together! Quartet' (団結！かるてっと, Danketsu! Karutetto) is the twelfth and final episode of the first season of Isekai Quartet'' and twelfth episode of the full series overall. It aired on June 25, 2019.

Summary
The mobile fortress "Destroyer" has joined the last game! It's up to the quartet to grab its headband and win the game.