I am really glad Razor brought up the Twelve, because this is something I've been toying with for a while...

What if the entities the beast tribes know as Primals and the entities that the people of the city-states know as the Twelve are not actually distinct beings?

We've seen that the Twelve can be summoned into this world through prayer (yours and Louisoux's pupils') and sufficient empowerment (there's a recent Lore Train entry where Fernehawles all but explicitly refers to Louisoux' staff as a "Key"). Gaius says much the same:
Quote Originally Posted by Gaius van Baelsar
Why not repeat the trick that worked so well at Carterneaux and call them down? They will answer... so long as you lavish them with crystals and gorge them on aether.
(cont.)