The MitD outwitting Xykon.

[veti]

Nuclear explosion? That would have vaporized the entire throne room, literally. And yes, the latter is a contrived coincidence, but since it doesn't immediately sway any of the important drama going on in that scene, it's not really that bothersome. The MitD has to find Roy's corpse for his tea party, so he probably would've found O-Chul's paralyzed body anyway.

I think 'nuclear explosion' may be hyperbole, but it was certainly a very large bang. Large enough to knock down significant portions of castle, at a range of a hundred yards or so. That makes it huge by conventional-bomb standards (a castle wall is typically at least 6' thickness of close-fitted stone), and I would certainly expect someone standing right next to it to be, at best, liquidised.

However, this is D&D, where you can make a saving throw to survive being hit with a 'Disintegrate' ray. My former DM had a house rule - more for amusement value than anything else - that any time you rolled a natural 20 on your saving throw, you took no damage at all from the immediate effect, no matter how apocalyptic. So to me, it seemed "impossible, but well within the spirit of impossible things that D&D allows".