Region B, spoilers and new concepts
If you don't want anything spoiled, do not READ THIS.
In Region B, the goblins are engaged in a holy war with rebel goblins and the goblin king is harranged at every turn by renegade bugbears. All the while, traps in every corner of the Region have forced various races to live in a smaller portion of the dungeon. A maze to the south, and the killing zone in the east central portion of the region, have become home to some very nasty undead. Vargouilles, ghouls, ghasts, and blink dogs are part of the stragglers.
While straightforward, the details behind this situation are complex.
First, the goblin king is really a doppleganger. The holy war is actually being fought over the statue of a goblin and not a "gift from the gods", and hobgoblin contingent, if left to their own devices, could wipe out all the goblins themselves.
The tension in this Region should be obvious.
If the PCs don't sense it, apply a few –2 circumstance penalty to fear saves.
On to the alternatives. Firstly, you can replace the goblins and hobgoblins
with gnols very easily, making the gnolls in Region C, off shoots of this tribe.
Second, replace the doppleganger goblin king with a low-level illithid who
is mind-controlling the entire lot of them. Remove the statue and replace it
with a hallucinatory shrine that helps to solidify the illithid's cause.
And his cause is simple, wipe out the bugbears, claim the region and then
turn his sites on Region C and the outcast gnolls there.
The howlers, blink dogs, vargouilles, and ghouls now become persecuted
creatures in the region. Add a few umber hulks to these encounters to
take advantage of the PCs weakened wisdom or to add some color to the
"misfit" bands, on the verge of being wiped out.
Of course, since the illithid is not OGL, we can't help you make stats for it,
but perhaps you can find information on it, somewhere.
Idea #2. Keep the rebel goblins, replace the Holy Goblin Empire with hobgoblin imperialists, and have the bugbears continue their raiding principles. Remove the blink dogs and howlers and add a small enclave of babau who have been unable to corrupt the gnolls, but are also immune to mind control.
This makes them a wild card.
Idea #2a. Lose the blink dogs, but give the howlers black orc riders (see Monsters by AEG) or some other race from your home campaign. Anything that can benefit from the howler's ability to reduce Wisdom is a plus.
Idea #3. Remove the rebel goblins and blink dogs. Replace them with spellstitch ghouls (from MM2), remnants of Azum's (see Region C) madness.
The holy goblin empire is then under a constant siege from enemy creatures and is more prey than predator. The doppleganger goblin king can be sympathetic OR perhaps he's already taken another form like a bugbear or the halfling bartlby. The throne would presently be empty and the goblins, all eager to prove their worth to take the throne, killing an elf or human to prove their prowess.
Idea #3a. Alternately a hobgoblin rules the goblins in some hegemonic fashion with the absense of their king.
Idea #4. Keep everything the same, but have the PCs arrive in the goblin empire (Room B75), just as the king is being assassinated, casting
Also note, the trapped rooms are good hidding places for kobolds and bugbears, both creatures with a natural tendency toward making/repairing traps.
More on Region E next time.
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