Natural Feature → Lair → burrow
Creature responsible: Monster → Rare → slime/ooze
Visibility: visible at great distance/focal point
Made with Ruby and Roda
For the curious, the source code is available on github.
Random tables from The Perilous Wilds by Lampblack & Brimstone
Adventure Generator based on "Random Sword & Sorcery Adventure Generator" by Ben Ball