Dungeon Ants

Ants in DnD editions have varied quite a bit so here are various ants of various sizes from pesky size to tank size, A really big ant hole might make a good dungeon if you can get rid of or live with the ants. 

I should do a monster book one day
They are not my thing personally but I have done lots now
What do ppl think of my monster format with variants and adventures?

Dont forget:
Ant abhumans of all types exist
Wereants among us I tell you!
Giant Stick Insects trick ants into raising their young
Antlions live near colonies acting as black holes on ants chemical maps
Some bugs even snails ride ants
Ticks on ants some good ticks eat bad ticks
Parasitic wasps might be at work on the colony
Some bugs smell like royalty and infiltrate and eat ants or waste or bully the queen untouched
The right scent can get you in an ant nest
Some scents drive ants crazy like hurt ants
Ants fight ants and termites

Intelligent swarms might have higher intellect as the size grows
Intelligent swarms might form shapes and seek to communicate

Swarm of Ants
Tiny Colony Insect
AC+11 HD2 Att 2 Mov3 enemies in one square range per HD take 2hp per round 
Crawling whole colony on the move often undermine ground that creatures can fall in. Fire makes the swarm make morale checks. The swarm of thousands or millions acts as a single living creature, all in area of swarm take damage automatically unless vacuum sealed 

d6 Varient Swarm of Ants
1 Army - especially aggressive that kill animals and roll over an area with several related swarms killing everything edible
2 Burning - damaged target save or lose d4HP and -1 all actions from pain for next d4 hours cumulative per fail
3 Swiming - can form a raft or bridge over water, each can carry an air bubble and may inhabit boats or flooded cave systems 
4 Stranger -  swarm may form a humanoid figure silhouette to spy on humanoids, may even wear clothes or human skin as a disguise
5 Devil - from hell can not be harmed by normal weapons unless silver or magic or fire, malicious and stinging that won't heal without magic or application of holy water before natural healing works
6 Master - these build structures including dungeons, sand traps, solar reflectors and plot against humanity and will capture and farm humans if given the opportunity and learn rapidly some colonies even trade metal or coal for food

Giant Yellow Ants
Large Colony Insect
Worker AC+3 HDd4 Att 1 d3  Mov12 10cm long
Major AC+4 HD1 Add 1 bite d4+venom Mov12 30cm long
Majors have irritating venomous bite save vs each or -1 all actions for hour cumulative per failure. Climb on any natural surface. These ants eat all kinds of organic matter and live in jungles and thick vegetation and even inside trees. Most are workers 60% and majors are 30% in a small nest of 30-50. A nectar carrying variety remains in larders with a swollen belly of nutritious syrup and never leaves the nest unless carried by workers. The queen ants are helpless nectar fed egg factories and good eating for a dozen in a meal. They rarely conflict with people but aggressive colonies may invade a dungeon and eat someone in bed then move and hide.

d6 Varient Giant Yellow Ants
1 Jumping - can leap 3m and drop on targets from above to hunt
2 Exploding - if killed explode for a d3 damage within 3m
3 Zombi - can hollow out a human or medium animal corpse and act as a zombie, when zombie killed ants swarm from its orifices and wounds to attack going on getting a new host
4 Spitting Ants - spit 3m range 1hp damage acid once each per day, often attack hidden  from vegetation or in rocks

5 Flying - this breed all have wings and build hives in high up places

6 Singing Ants - each group of four singing can cast a charm person spell per day with their eerie haunted buzzing chatter, the ants take thralls home to work for them bringing them food and helping to improve their colony

Giant Red Ants
Huge Colony Insect
AC+4 HD2 At 1 d6 bite Mov 12 Climb 6 Fly 24
These ants range from large dog to human size and are good climbers but too heavy to hang on some ceilings or branches and they prefer digging and underground lairs. These are the most common giant ants people meet in dungeons and the Sunderland and some colonies are enthralled or tamed and in some places, these ants domesticate humans. These ants have the most variety of types and subspecies. Young kings and queens have major like mouths that do a d8 and they can fly and sometimes try to nest in places humans don't approve of. Driving off the king and queen early helps. 

d6 Varient Giant Red Ants
1 Fire Spitting - can spit fire once per day 2d4 in a 90 degree cone range1, majors can breathe fire every second round
2 Venomous Ants - have an extra d4 stinger attack save or d4 damage per round for d4 rounds 
3 Berserk - AC+5 HD4 Att1 Bite d12 once bites hangs on biting automatically each round, even when killed and heads cut off for up to -10HP
4 Farming - these capture humans and other animals as livestock but find humans the best, they grow crops in fields and some human pets get to be farmers
5 Mushroom - cultivate fungus farms and forests and keep giant worms and other creatures

6 Host - cany d4 huge ticks use yellow ant stats that attack anyone killing host, they steal food from ants mouth and make ants weak and waste time trying to remove them or find some other critter to remove them

Giant Black Ants

Giant Colony Insect
AC+7 HD8 At 1 bite 2d8 Mov 12 Climb 6 Fly 18
These are oxen sized and very intimidating and thankfully rare. Winged adults establish new colonies and these monsters could destroy civilisation if allowed to thrive.

d6 Varient Giant Black Ants
1 Iron - AC+10 metallic chiton armour and +2 damage
2 Acid - spray 4d8 acid once per day 12 range, all in 2circle splattered for d4, save halves the damage
3 Intruder - experts at stealth and develop local camouflage such as logs or mass of vegetation or rocks making them hard to find or avoid
4 Spore Ants - infected by colonial fungus makes ants fearless and farm fungus they eat and infect selves with until collapse into a mass of rotting fungus
5 Antlered - fungal antlers from mind control parasites will use ant to capture victims to infect with the antler horm. Save if touch antler or infected, each week save or antlers sprout and influence dreams and occasionally find hallucinating what you did when your body did other things. A second weeks failure makes the victim a total thrall of the fungus and go serve the ant who infected them
6 Undead Ants - made to serve a necromancer with all benefits of undead status

Guargantua Ant
Gargantuan Insect

AC+12 HD40 10d8 Mov24 
These titanic ants easily destroy buildings and towns and thankfully are not seen in colonies. 

d6 Varient Guargantua Ant
1 Web - can spit effect of a web spell three uses per day

2 Energy Beam - 100 range 6d6 energy beam from the antenna
3 Gas - if angered all in 3 range hit by choking gas 3d6 half if save if breathed
4 Carrier - can drop a swarm of ants per round who protect their god loyalty
5 Builder - will dig a huge home structure of wood, silk, logs with an underground tunnel complex, if controlled can be very useful for construction or build on top of the ant
6 War -  ant abhuman warriors with spears ride a building strapped to the ant. A dozen archers with composite bows and another dozen with long spears who protect the ant from enemies getting on the ant. Abhuman wizard ant or ant hero usually command and a specialist driver is seated under the chiton against the ant's brain

d12 Ant Adventure Hooks
1 Some loner shacks have been found shattered with no bodies found

2 Someone saw two giant flying bugs land on the hill and crawl in a cave, found these huge wings left behind at the entrance

3 Giant bugs in fields have been nipping at workers who can't find nest and are afraid to go to work

4 Some miners have returned from a quarry with ants on their backs with pincers around their necks, they demanded food or they would die then left

5 An evil wizard threatened a castle with destruction and inhabitants laughed, then the wizard returned with a gargantuan ant servant

6 A sinkhole opens in the street swallowing up an ox, people all stand around the dusty pit trying to see what caused this

7 Child is found lost and in shock, a local points out a farm track and the farmhouse is ruined and abandoned

8 Several men left the tavern, someone heard them yelling and looked but saw silhouettes moving away in the mist. In the morning men's clothes left and some blood

9 Ant people riding giant ants have been seen in the hills up to something 

10 Some dungeon kobolds will pay hunams to get rid of any in the dungeon will pay in gold and magic mushrooms and potions or even a dungeon room lair

11 A prospector discovered he could trade food for gold nuggets with ants and told a gang who have enslaved the ants. He wants the criminals stopped and ants rescued

12 A strange earth wall appeared around the village overnight with roads blocked and various pits and hidden pit traps have appeared. What is going on