A small group of cannibals has started roaming farther out from their remote home and have come into contact with some farms.
The heroes find a small crypt somewhere and being brave adventurers they want to check it for evil forces (=graverobbing). Or for any other reason.
As a mage walks through the forest a sprite appears on a branch in front him (or her). The mage will be the only one that will be able to see the sprite. The sprite demands that the mage release him from the forest.
On the outskirts of a poor looking village is a large mausoleum that is well kept and richly deserted. It has a marble walkway and bricked windows with beautiful ironwork adorning it. For grave robbers the look of the outside tells of untold riches on the inside.
In a village the characters hear rumors of a man that recently came through screaming of demon attacks and murderous insects.
A large explosion was heard 4 days ago coming from the foot of the nearby mountains. Ever since then no trade wagons have come through as they usually did.
The PCs are exploring the catacombs beneath a Colosseum-in-Rome type of structure, when they come across a foul-smelling, stagnant, ankle-deep with algae, public mass latrine. Countless urinals of marble, line this rather large chamber equally crafted of marble. Whatever system of plumbing once worked here, has not in many years. Old graffiti lines the stained,dirty walls, prominently bolded are such intellectual poetic musings as, "Urine For It Now", "I Pee Therefore It Comes" and "Now Urine Trouble".
A few moments after the PCs get to take in this unpleasant location, they hear the low rumbling of ancient plumbing and rather large Urine Elemental rises like a great, wet, wave of filth to attack them. The creature reeks and exudes noxious debilitating fumes, while its liquid strikes burn flesh like acid.