So, I'm not entirely sure what inspired this, but I've come up with an idea for a special dungeon/encounter with its own special miniboss... an Impostor Basil. The whole thing would randomly, rarely, take the place of the normal mid-way point rest level.

The idea is that, at first, there would be no hints that anything is wrong. At least nothing too obvious. The level would have the same name as normal, you'd go in and there'd be the mineral deposits (they might only drop the tiniest size, though) and there is "Basil" waiting next to the health restoring pads...

If someone talks to "Basil", it will open up the vending menu as always, and.. maybe something is off about the selection. There will only be weapon recipes, no armor or helms. Maybe there are recipes for items that don't even exist. Maybe there's some nonsense about guaranteed UV's in the recipe descriptions. Maybe the prices are just wrong somehow. If a player attempts to buy one of these recipes, it will immediately close the vendor window (for everyone. And nobody actually gains any recipes) and "Basil" might say something along the lines of "A very good choice. I happen to use one of those myself; here, let me demonstrate it!" Immediately the appearance of "Basil" will change, becoming something more sinister looking and not quite Basil-y, and the impostor will pull a gun or sword or bomb out of his robes and attack the player who attempted to make the purchase, initiating the battle..

Alternatively, if nobody attempts to buy anything and instead all proceed to the elevator, a trap will be sprung; gas will be pumped over the elevator, inflicting a lengthy stun on all of the players, and "Basil" will say something villainish about how they fell for his trap as the battle starts anyways.

Impostor Basil would move fairly slowly, and employ a variety of different attacks as he pulls weapons from within his robes. Melee attacks, ranged attacks, bombs, most of which probably resembling charged attacks that weapons the players can get do. He may also have some manner of INCREDIBLY insidious attack in which he attempts to steal large chunks of crowns from a player! In addition to all of that, various enemies will spawn from the direction of the elevator the players came in from and wander their way up to the battlefield. If that wasn't bad enough, I was thinking that these enemies, when defeated, might sometimes drop some sort of DEVIOUS TRAPPED FAKE HEALTH PICKUPS that damage instead of heal when grabbed. (they would of course have some kind of visual difference to tip the players off)

Additionally, at some point (perhaps when he reaches a certain level of health) The health-pads (which of course become deactivated or even hazardous the moment the battle starts) will be replaced by gun-puppies.

When this impostor is finally defeated, he should drop a number of FREE RECIPES for the loot; quite random (and of course limited in their tier by the dungeon tier the fight occurs in. There could definately be tier 1, tier 2, and tier 3 versions of the encounter, of adjusted difficulty) but potentially extremely valuable, but then it would have to be for the inconvenience and trouble the players have "suffered" by getting a mini-boss where they were expecting a rest stop, and also making up for the fact that they never actually got the chance to BUY recipes (and may have had some crowns stolen during the fight).

Of course, his drop table would also be a great place to include some sort of ultra rare drops (like a Stranger mask helm?) or unique recipes unavailable from the REAL Basil.

It will also never be explained whether this impostor is something fiendish or gremlin built or even an actual stranger with a grudge against the Knights... of course, the real strangers will vehemently deny this latter option.