Smoke in the Glass

A world of immortals living among humans. Anyone may be immortal, but there is no way to know until you die. If you are one of the very lucky few, you will live an endless life of pleasure and power, considered to be a god. Only decapitation and the rapid separation of body and head for a few days can kill an immortal.
In the southlands, a common soldier dies and is reborn, and is inducted into the world of the immortals. But the Empire has become decadent, and what he discovers there will shock him.
In the dry lands of the west, one man has set himself up as the sun god. But there is a prophecy that he will be killed by his son - and so all of his male children are killed at birth. Until his most recent wife bears a child who is nether male nor female, and is determined to protect them from sacrifice.
In the cold north, the immortal Luck - clever, tricksy, clubfooted - harbours suspicions that many of the immortals have been killed. When he intervenes in an attack on one of his fellows, he realises something new. Someone is hunting the Gods.
For there is a fourth land. They know of the other three. And they are planning their attack.
Our three heroes - damaged soldier, protective mother, clever cripple - must find a way to unite their different lands, and defend against this new enemy.