Isekai Cheat Magician
Episode 6
S1 E6:
After defeating the golem beneath Azpire Taichi and Anastasia encounter the young magicians Milo and Melo, who command a large horde of Red Goblins. Meanwhile Rin and Muller alert the guild to an impending attack from an army of several thousand monsters. A dour mood hangs over everyone there, but Rin and Muller resolve to defend the city. Luckily that's when Lemia arrives, having sensed something wrong within the city...