OK, I've been having some discussions about the ramifications of adding MtG worlds to the D&D cosmos with @slobster and @Urriak Uruk and it got me thinking. What would a unified cosmos look like that blends elements of both, yet allows them to be separate. Here is what I came up with:
- The Blind Eternities from MtG are analagous to the nebulous "Far Realm" in the D&D cosmos. Though the image makes it look like it is a vast space, it is not. The Blind Eternities area a sublime shadow. It is not space or a place, but the concept between space and reality. Here the be aberrations (including Eldrazi). Passing through the Blind Eternities is nearly impossible. Typical spells do not work, and even planes walking is almost inconceivable through the depths of the Far Realm. Gods can travel through it with great effort, but doing so attracts the attention of the Eldritch Titans (Eldrazi, Azathoth, etc.) and it tends to damage the boundary between a reality and the Blind Eternities, allow aberrations to infect reality.
- The Border Realities are areas were the Blind Eternities are weaker. They are created by the close conceptual proximity of separate realities. Most magic (plane shift, gate, etc.) will not penetrate the border realities; however, planes walking and some very power rituals / magic might. A door in Sigil might lead to Athas or Eberron for example, but it couldn't reach the Aether Realties.
- The Great Wheel reality is the general reality of D&D. Any world / plane that can be reached by a spell, such as teleport, gate, or plane shift, in D&D is in this reality.
- The Athas reality exists in the border reality of the Great Wheel. It is in close enough "orbit" that powerful magic can allow travel between the two, but not standard spells.
- The Eberron reality exists in the border reality of the Great Wheel. It is in close enough "orbit" that powerful magic can allow travel between the two, but not standard spells. It might be slightly further out than Athas, requiring even more powerful magic to reach.
- The Aether realities are all the planes from MtG. Their close proximity to each creates a border reality that allows planes walking between these worlds. The Aether realities are in the abstract "orbit"of the Great Wheel reality, but they are so far out that the vast metaphysical space that separates them makes it virtually impossible for planeswalkers or deities to travel between the two.