The #RPGaDAY prompt was concocted by Dave Chapman of Autocratik. Grab the list and join in!
In the midst of Carrion Crown‘s Wake of the Watcher chapter, beset by nightgaunts and mi-go, we happened across a creature sufficiently bizarre to put all the Lovecraftian beasties to shame. It hopped. It squawked demanding, nonsensical questions. It projected images between antennae. It was . . . the riddling turnip. Or really, it was a cerebric fungus. But the WTF factor of the encounter stuck with us for weeks after, past the mi-go’s Mr. Chunder blender, Gea the inside-out mockery of an eidolon from beyond the Dark Tapestry and even the incarnation of Shub-Niggurath herself.
“They must have ordered it late one night off the electric radish.”
— Geoff on Mr. Chunder
Honorary Mention
Way back in the day, there was the Stargate SG-4 campaign. This team of four tromps through the gate to a shiny new world, discover it’s the middle of the night in a museum and they immediately panic. Run! Hide! Don’t let the aliens find us! Never mind that this is the Stargate universe, where a simple “hi” works wonders. No, some primal groupthink instinct kicked in and the team members were all seized by an utter dread of actually encountering any inhabitants of this world they’d come to explore.
Held Action 
I finally move past the nightmares, and you go and bring up Mr. Chunder again.
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