Encounter background (1d6):
Morlocks* in the service tunnel network below the ruins of a city of a future past.
*Of course, those can always be changed into a different kind of degenerated underground dwellers.
1# The pipes are calling
The characters move through a series of narrow, rectangular tunnels whose walls are lined with old pipes of varying diameter and pass junctions and crossings. Now and then, a clanging noise can be heard that resonates through the metal pipes. The players might already guess that these are a kind of signal or code, but unless their characters pass an ability test vs. Intelligence, they will not note that there are actually two groups exchanging signals and that, after a while, the second group now signals from behind them. There are 1d6+2 Morlocks in total who will try to ambush them into a long corridor so that they can attack them from two sides.
2# Fan service
Passing through the corridors below the city, the characters will hear a loud noise ahead of them: the banging of metal on metal as well as other sounds. In a cylindrical ventilation shaft that lies further down the corridors, 1d3+1 Morlocks are trying to bring a large ventilator back to work by exchanging some rusted, mechanical parts. The broken parts, they let drop down into the darkness below them. While one of them was meant to guard the other/s, he stares fascinated at the dismantled, giant apparatus. Thereby the characters have a chance to suprise the Morlocks. All of them are armed with heavy tools that count as clubs while the guard carries an old fireaxe.
3# A nest to rest
While the walls of the corridor the characters are in is lined with plastic panels, ahead of them 1d6 Morlocks have removed said panels so that each of them could form himself a “sleeping nest” in the wiring and cables beneath. The recess they thereby created is deep enough that they cannot be seen from the corridor at first, the underground dwellers will for sure note any light source the characters might carry. Once awake, the Morlocks will wait till the characters come near before they quickly jump out of their “nests” to attack the intruders with claws, teeth and knives. The PC will need to check for surprise.
4# Dinner bells
The characters will come to a door that was barred from the inside and the odor of an old fire hangs in the air. If the characters force the door open, they stumble into an improvised “smoking chamber” the Morlocks use to cure meat, and the slaughtered remains of 1d6 animals of different size as well as 1d4 mutant humans dangle on crude hooks from the ceiling. But the moment the door is opened, the sharp ringing of an alarm bell is audible from deeper inside the complex. The door was rigged with an improvised electrical alarm, a cable runns visibly from the door through the room and an empty door opening on the other side and further into the darkness.
5# Hunting grounds
A huge jaw trap with a bait in the form of a large bone with scraps of meat on it rests in the center of the floor (or room) the characters enter. More of those traps can be found in the surrounding rooms and corridors, and the chance of an encounter with one or more Morlocks is increased in this area (as the hunters tend to check their traps from time to time).
6# Ape alarm!
Out of the dark, the characters are suddenly attacked by a loudly screaming albino ape. But before he can reach the PC, he is stopped dead in his tracks by a chain and collar attached to his neck. The angry beasts bounces back, its screams and shouts echoing through the dungeon-like underground. If the characters do not turn round and leaf the area, they will soon encounter an alarmed group of 2d6 armed Morlocks that will come looking for their “alarm pet”.