The Beyond

The Beyond is The Somewhere Else where souls must go.Arcanum Unbounded, pg. 206
Preservation tells Kelsier that this is where his soul must go. Further, that it takes longer for Allomancers, but it will happen. That it is the natural progress of things.Arcanum Unbounded, pg. 206
All sapient entities transition to the Cognitive Realm before going to the Beyond.Mistborn: Secret History This includes Ryshadium.Oathbringer release party, Provo, UT, 11/13/17 However, if one initially refuses the call of the Beyond, it still may change later.Stormlight Three Update #5, 11/18/16 
Within the cosmere, there are forces derived from Adonalsium, and forces derived from without. One is a force that opposes Adonalsium - which still exists - and some say there are "subtle forces" being manifest, separate from Adonalsium, perhaps referring to the God Beyond.Brandon Sanderson AMA 2015, 17th Shard, 3/12/15
==Notes==
According to Brandon, the Spiritual Realm is not the Beyond. Further, that there are philosophers who would say, the Spiritual Realm and the Beyond are one, that the soul gets sucked into and joins the Investiture. That this is the idea of the One. But, most people would say that the Beyond is not ... .Arcanum Unbounded release party, Provo, UT, 11/22/16
==References==
Category:Cosmere