Who doesn’t know? It’s something like Pokémon, but with monsters borrowed from all the mythologies they could remember.
It’s roughly like this:
I especially recommend paying attention to Grigory Efimovich Rasputin with the combat matryoshka (on the right).
And some other stuff...
And there’s also a completely amazing design of the Buddhist prince of illusions, Mara, but I won’t post it here, or I’ll get banned, and rightfully so.
Just Google kazuma kaneko mara and enjoy.