More specifically I was refering to the novel War of the Spark, mostly set on Ravnica and to a much lesser extent, Amonket.
It involves Ravnica Guild politics, most Planeswalkers, all kinds of Eternal Zombies which are like mummies coated in a special mineral (including Eternal Angels, Eternal Demons, Eternal Minitaurs, Eternal all Amonket races, and Eternal Gods), ect...,
In many ways it renders Guildmasters Guide to Ravnica obsolete (the book should have been writter after these events).