Isekai Quartet

Isekai Quartet is a Japanese anime series. The series is a comedic crossover between four light novel series: Konosuba! God's Blessing on This Wonderful World, Overlord, Re:Zero -Starting Life in Another World- and The Saga of Tanya the Evil. Two more series (The Rising of the Shield Hero and Cautious Hero: The Hero is Overpowered but Overly Cautious) were added in the second season.