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D&D 4th ed: The Thoon Campaign: Dark Secret of the Gods

So now it is time to tie it all together, and give one possible explanation of what Thoon is. I think you will like it; after all, it ties together three very real elements of the new D&D cosmology and makes for a compelling campaign background, one which is both plausible and involves a lot of adventure.

First, lets take a look at two new factions in the D&D universe, the Shardminds and the Quom.

Turning up in the Players Handbook 3, the Shardminds are beings composed of fragments of living crystal, a crystal that once formed the body of a titanic Living Gateway between the Astral Sea and the Far Realm.

The gateway had existed, hidden away in the astral sea, since long before the Dawn War, and it was guarded by a powerful being, neither god nor primordial, who prevented anyone from opening the gateway or even looking into the realm of madness beyond it.

Legend has it that three gods came to the gateway. Pelor found it (and later wished mightily that he had not), Ioun investigated it and mistakenly woke the living gateway from out of its ancient slumber, then The Nameless God (possibly the original god of Humans who was later killed by his own angels, his home becoming the Nine Hells) distracted the gateway's guardian long enough for all three gods to get a good look through the gateway.

The three gods fled, vowing to never speak of what they had seen, or seek out the gateway again.

That would have been the end of it, but for the chaotic events of the Dawn War, when gods and primordials fought for dominion. It was at the time when the war was most desperate and the Nameless god decided to break his vow, sought out the gateway and did battle with its guardian. None know why, but it is certain that the Nameless god killed the gateway's guardian and the gateway responded by opening.