A King's Commission leads to danger! All communication with the barony of Twolakes Vale has ceased. King Ericall, worried about the security of his border and angered at the loss of tax revenues, has commissioned you, a delegation of powerful characters, to investigate. This is not a petty problem to be solved by the armies of local nobility. Indeed, the king's forces are desperately needed elsewhere. Twolakes Vale is, after all, only a small barony on the far frontier of Ericall's domain. And yet... The cloud is there, its nature and cause unknown. None have returned from the barony for weeks. Furthermore, the cloud is spreading, and vague reports of unrest and mysterious disappearances are starting to trickle in from nearby baronies.
A pretty interesting adventure that often surprises you with how relevant some of the advice still is. It discourages you from letting your players having too many followers as it will bog down play. It allows for what happens if your PCs just turn around and go home. And your players can theoretically do any of the adventure sections in any order
Creativity from yourself and your players is encouraged at every turn because it understands that that's where the best aspects of any game comes from. As written the Big Bads are a little forgettable, and at times encounters vary wildly in difficulty. But the story is interesting enough and for a $3 pdf on Dmsguild or a lovely present from a secret santa you could do a lot worse.
This is another adventure which is hard to judge by today's standards, without familiarity with high-level "BECMI" play. The plot requires some additional nudging/fill-in by the DM, and it seems like the encounters would be pretty deadly for non-magic heavy parties. However, it's an adventure for 6 15th-20th level characters, so it should be hard! The editing could have been a bit better but overall, there are ideas here that could be adapted to a modern style gaming session, with some work.