The of Kadokawa has a trailer for an official crossover of KonoSuba, Overlord, Re:Zero & Youjo Senki (Saga of Tanya the Evil). : r/Konosuba

Isekai Museum in Japan features Re Zero Overlord Konosuba The Saga of Tanya the Evil 0019 - Anime Trending

Konosuba,' 'Overlord' Anime Crossover Reveals New Poster, Release Date

Isekai Quartet, Isekai Quartet Wiki

Isekai Quartet, Isekai Quartet Wiki

I feel like the Overlord community is the only one who appreciates Isekai Quartet : r/overlord

Konosuba,' 'Overlord' Anime Crossover Releases New Trailer

Isekai Museum in Japan features Re Zero Overlord Konosuba The Saga of Tanya the Evil 0011 - Anime Trending

The Saga of Tanya the Evil Season 2 Announced : r/anime

I feel like the Overlord community is the only one who appreciates Isekai Quartet : r/overlord