Fantasy book about supernatural beings that can take drugs to get into a different world

Question

I am looking for the title and author of a book I have once read in the fantasy genre. The novel is probably published after 2000.

I remember two specific elements: the first is that the protagonist, a male, is part of a group of special beings/half gods. I believe they are called the immortals or something like that. There is a fixed number of them (a hundred perhaps?) and each has superhuman abilities, but all have different ones. I believe the protagonist was very fast or could fly, but I am not certain. Now I seem to remember that sometimes people are promoted into this group, but I am not sure and how it worked, perhaps if a member died or something.

The second element I remember is that you could take a substance that transported you to another world. Like hallucinating, but the world you hallucinated was real and persistent.

A last thing, which unfortunately I am not certain of as I read many books, is that the author might not have an obviously male or female name, at least to a non-native English speaker like me.

This is the sum of my memories about the book, next to the fact that I enjoyed it. I am looking forward to your answers.

Answer 1

This sounds very like Steph Swainston's The Year Of Our War

Jant is the main character, and he is one of a circle of immortals - these are people who each have a specific power; Jant's power is that he can fly, and is the Messenger. The immortals are the best at what they do - I believe that when a vacancy arose, there was a competition to determine who was the best, and that one became the new Immortal.

Additionally, Jant is taking a drug that lets him access an alternate world. It's either a real world or an extremely vivid hallucination; and he can't be sure which world is actually the real world.

There are apparently a three more books after the first one, so you have some catching up to do!