: The armies of the Dark collapsed after Balor was killed.
: Each of the Fallen Lords were bound to him in some
: way. Without him they were much weakened as far as I
: can tell. There are also no accounts of fighting after
: Balor's head was thrown in the The Great Devoid.
: The best evidence I have, though, seems to be this:
: "Today the Dramus River is frozen solid, but back
: then it was a muddy torrent of melted snow and ice
: brought on by the eruption of Tharsis. The Deceiver
: was plunged into the river and swept far downstream,
: his scepter sinking to the bottom."
: Journal entry from "The Stair of Grief"
Perhaps it wasn't the Light who trapped The Deceiver in the river at all, it may have been another one of the fallen lords. They all seriously disliked The Deceiver, and perhaps one of them ran into The Deceiver somewhere in the west, and had it out with him, since Balor could no longer control them. So, The Deceiver flees back to the Stair of Grief, sets up an ambush, kills the other fallen lord, but in the process gets his army killed and is swept into the river. The rest of The Deceiver and the other fallen lord's army are left wondering what the hell is going on, fall upon eachother, leaving just a few scraggling survivors for Alric and the armies of the west to hunt down.