MitD VI: The Undiscovered Creature (Please Read the First Post)

[balladfen]

Just to be clear, I'm not trying to say that "RedCloak's EvilKitty Umbrella of Small Radius Magical Darkness" is impossible either, but let's look at the assumptions you need to make for each case[...]

The way I'd look at it, the assumptions are:
1) The characters in OotS can and do create new spells and magic items and alter old ones, or
2) There is an ability of some kind which transforms mundane shadows into impenetrable magical darkness.

I think both are equally possible, but the assumption necessary for the former isn't so much an assumption as a repeatedly-demonstrated fact. The latter requires only a single sourcebook I haven't read, but the fact remains that it's an assumption. Until we have an explanation--some creature with that ability, some spell that does it, something--the existing explanation remains less of a leap.

EDIT: Once again, I have been made redundant and irrelevant by slow typing.