Recently, it seems to have been confirmed that the Pale Summoner in the Diablo IV cinematic trailer is actually Rathma, son of Lilith. So, if this is true (which it certainly seems to be), what does this mean? Consider this a brief lore check on who the legendary Rathma is, and why his appearance is important to the story – as well as incredibly confusing.
Rathma is a first-generation Nephalem, a race created through the mating of demons and angels. This lineage gifts the Nephalem with incredible power, so much so that the weakest Nephalem is still more powerful than the vast majority of the races that spawned them. Throughout time, the Nephalem would slowly have their power dilute as they reproduced, eventually becoming the comparatively-puny Human race. As a note, the Diablo III adventurers are all Nephalem, which is canonically why you can beat the Prime Evil in a fistfight.
A powerful summoner, Rathma fought against both of his parents in the Sin War, the subversive cold war that Heaven and Hell fought over Sanctuary. He believed in ultimate balance and wanted Humanity to control their own fate, and partnered with the mythical creature Trag’Oul to work towards this goal.
To work to preserve this peace, Rathma would found an order of followers known as the Priests of Rathma. This order is what the Diablo universe comes to know as Necromancers. As time goes on, Rathma and his necromantic priests would successfully hold off those trying to ruin the balance of Sanctuary.
As the Sin War continued, Lilith would be banished and the war would ultimately end in a stalemate. Rathma would eventually fade from prominence as the race of humanity had their memories wiped at the conclusion of the Sin War to allow them to live in “peace” without knowledge of angels or demons – both of whom would ignore this point and continue to meddle with Sanctuary.
The confusion comes in at the question of wondering why Rathma would begin the events of Diablo IV by resummoning the woman that he helped to banish. One thing we know about Rathma is that his main concern, and that of his necromancers, has always been a balance in all things.
Is his intention to summon Lilith back into Sanctuary to help restore the balance? Does Rathma intend to work towards the betterment of humanity again, or has the human race gotten cocky after the defeat of the Prime Evil and Maltheal? Or is Blizzard maybe just doing their favorite pastime of retconning large amounts of lore?
It’ll be quite some time until we finally see Diablo IV. Until then, we can hopefully look forward to more trailers and tidbits of information to help piece together why Rathma has returned – and why he’s so eager to reunite with the woman he waged war against.