Drakauthix

 One thing i will always praise paizo for is throwing in some outright weird monsters in their books. The drakauthix (please don't make me try and pronounce it) is one of those things. A giant, floating, carnivorous tentacled mushrooms that see through clouds of spores. And i'm bloody loving it.

Rotten hill, the windiest peak in all of Ungerlund, is now home to a crazed fungal monstrosity. The spores of a juvenile somehow left their dark, underworld homes, and hatched on the sunny hill. However, the constant heavy wind that blows across the entire area keeps sweeping away any sight-spores. Hence, the drakauthix is crazed into being less passive than most of its kind, violently lashing out at any motion it manages to detect in its close vicinity. As the hill is a popular spot among locals, the Duke has offered a reward to anyone willing to cleanse it.

Explorers under the leadership of Ser Henry Hearthwise have achieved their goal - they reached the famed bottom of the world. Except, after going several hundred kilometers underground, discovering several lost civilizations, and going through caverns no mortal eye has ever seen... they're in for one more surprise. What every civilization since the creation of the universe has considered the endpoint of the world itself, is in fact populated by a sea of flying, tentacled mushrooms. Ser Henry being who he is, some foolhardy shenanigans net him a discovery that will shake up all theories about the world - beneath the shroom colony, a deep and dark abyss lies... and the fungal beings seem to be feeding on the remains of whatever lives below.

The king has been killed, and very creatively. Someone managed to slip live drakauthix spores into the ink that was delivered to the king's scribe. Soon enough, several of the fungal behemoths rose up across the castle, most notably in the king's bedroom. A rescue party must go into the keep and find any remaining survivors, while also trying to contain the infestation.