An Adventure for Every Monster - Ant, Giant

This adventure takes place in a section of city sewers or a quiet area of the dungeon where there is an underground river. A colony of giant ants has made its nest here and now they have got onto the wrong side of a pack of giant rats, led by a group of were-rats who are trying to flood them out by building a dam and diverting an underground river or sewer.

The ants will try to use their hive mind to contact the party to see if they can take on the rats and save the ants’ nest. The ants will offer any treasure that they have to the party as reward (the ants have no need for it but they know that humans value it). This contact may take the form of crude telepathic communication (images and suggestions) or – if you want something truly memorable - the ants can use their smaller brethren to move corpses around using manipulation of muscles, pumping of lungs and tweaking of vocal chords. It might make an interesting sight if the party mistake this for a zombie or some such. They may also try using scratchings on the walls of tunnels or arranging detritus into arrows or basic symbols. It’s up to the DM to judge the form of communication that the party would find intriguing but not disregard. The ants, if encountered and attacked will not respond with violence but retreat back towards the nest.

The closer to the queen the party gets, the stronger the telepathic communication will get, accompanied by pheromonal messages to amplify the meaning.

The approach to the queen also means that the tunnels leading to the ants’ nest get smaller and smaller until they are at most a foot high or so. In places, they are littered with bones still within armour, discarded weapons and gems and coinage.

The ants’ offer may also include tracking down and bringing back objects and treasure that is in areas generally inaccessible to humans, either through space or hazards which humans cannot endure or confront.

The ants have their nest directly over the location of a set of Pipes of the Sewers that the were-rats need to unleash chaos on the city and profit thereby. It is quite a dig (30 feet or so) down to the location of the pipes, which are in a catacomb in a small temple, blocked by collapsed tunnels and rubble for more than a century. The catacomb is protected by a clutch of skeletons, who will activate if anyone crosses the original threshold. A precisely targeted shaft will come straight down into the catacombs, a misaligned one will come through outside and the intruders will have to cross the threshold. The skeletons are armed with blades that are covered in a weak poison (save at +2).

As well as the skeletons and the Pipes of the Sewer, there is a secret door that leads to a flight of stairs down about forty feet to a tunnel that is also blocked by rubble, although in this case, permanently. On the walls of this tunnel are a number of very old paintings that show a series of clues to a dungeon complex elsewhere below the city (if setting this adventure in a section of dungeon, the clues are to another section that the party has not yet encountered)

If the party either chooses to ignore the attempts by the ants to communicate or actively attacks the ants’ nest, the work of the were-rats will be considerably easier. They will unearth the Pipes within two months and their rat attack will begin thereafter, with imaginable consequences. The party may become involved in efforts to resist them.

And yes, we will be having adventures for rats and were-rats in their own right later in the series.

Ants, Giant
Frequency Rare
No appearing 1-100
AC 3
Move 18”
HD 2
% in lair 10%
Treasure type Q x 3, S
No of attacks 1
Damage per attack 1-6
Special attacks Warriors have poison sting
Special defences Nil
Magic resistance Standard
Intelligence Animal
Alignment Neutral
Size S (2’ long)

Treasure type Q gives an even chance of 1-4 gems and type S offers a 40% chance of 2-8 potions. If the DM wishes to change the treasure type to reflect that garnered by fallen adventurers, it might be an idea to change it to one roll of each treasure type J to N, multiplying the results by 10 or even 20 to give a reasonable haul.

Whilst the MM tells us that giant ant eggs have no market value, there may well be a demand for them as an ingredient in the potions of alchemists and apothecaries.

Giant Rat
Frequency Common
No appearing 5-50
AC 7
Move 12”/6”
HD 1-4 hit points
% in lair 10%
Treasure type C
No of attacks 1
Damage per attack 1-3
Special attacks Disease
Special defences Nil
Magic resistance Standard
Intelligence Semi-
Alignment Neutral (evil)
Size S

Treasure type C, as we saw last week, is a low-probability broad coinage and gem spread type which could mean that effectively, depending on the rolls, the rats and their were-rat masters have no treasure. It might be an idea therefore to assign treasure by character rather than using the rat and were-rat treasure type. The rats would have had any loot taken from them by the were-rats anyway.

Were-rat
Frequency Uncommon
No appearing 4-24
AC 6
Move 12”
HD 3+1
% in lair 30%
Treasure type C
No of attacks 1
Damage per attack 1-8 (sword)
Special attacks Surprise on 1-4
Special defences Hit only by silver or +1 magic weapons
Magic resistance Standard
Intelligence Very
Alignment lawful evil
Size S-M

The were-rats are three in number, the original infector, a thief who was injured and his colleague, who he lured to the sewers, once a cleric but now fallen and working as a fighter since the defection to lycanthropy. They have their lair in a cluster of small rooms that once formed part of a catacomb but have long since been cleared out. They are connected to the sewer (or main dungeon corridor) by a crudely hacked tunnel, the sides of which may still show a protruding bone or two (and the slim possibility – 10% - of some trinket of jewellery, worth at best 2 d20gp.

The DM may wish to roll randomly for the phase of the moon or have it that extreme stress triggers a change into the rat form.

Original were-rat (stats for human form) – former magic user
S 9
I 16
W 10
D 13
C 9
Ch 9

Level 2 (2 x 1st level spells per day)
HP 6
AC
Weapons – 2 daggers, set of throwing darts, staff

Spellbook contains

9 x 1st level spells
1. Push
2. Magic Missile
3. Hold Portal
4. Jump
5. Spider Climb
6. Light
7. Identify
8. Write
9. Ventriloquism

This character will also have a collection of pestles and mortars, alembics, flasks, burners etc in his lair where he is concocting new forms of poison from the moulds, fungi and growths found in this area of the sewers. He has found nothing so far that will have an effect on the ants.


Thief (stats for human form)
S 17
I 7
W 11
D 15
C 16
Ch 8

Level 2
HP 12
AC 6 (Studded leather, shield – includes DEX bonus)
Weapons Short sword, dagger x 2, sling and bullets
The thief has a penchant for silver jewellery and there is a collection of this hidden in his quarters – the total value as silver scrap is 250gp but sold as individual items, could raise three times as much.


Former cleric (stats for human form)
S 14
I 12
W 16
D 8
C 10
Ch 9

Level 2
HP 10
AC 2 (plate mail plus shield)
Weapons – Footman’s mace, staff.
(note that it may be the case that the cleric, having fallen from the service of his deity, can use edged weapons. This is a decision for the DM to make – if this is the case, the cleric will also have a longsword +1)

The former cleric is torn between the delights of his new form and anger at the loss of access to deity and spells. This has become twisted in his mind and the walls of his quarters are now covered in charcoal renditions of a rat deity that he is coming to believe actually exists (it may be that there is such a deity in the DM’s campaign, in which case the cleric may attract its attention soon – for good or ill)