One of the dangers of the grasslands of Wampus Country is the presence of the Myrmida, also known as 'ant-men' or, more popularly, 'mants'. These large insects live in expansive colonies with populations in the hundreds, and their belligerence is well-known.
A mant is a bipedal, ant-like creature between three and five inches in height. Its chitinous shell may vary in color widely, but all mants of one colony look similar. They may amble on two legs, or sometimes go about on 'all sixes' as necessary. The pinching jaws of a myrmida are fierce indeed.
The mants are intelligent tool-users, and have developed a very strange culture. Each colony manifests a low-level telepathic field centered around the Queen, enabling a kind of hive-mind. But beyond this, the mants themselves carry within them a kind of 'race-memory' repository of long-dead cultures and knowledge. A colony subconsciously accesses this race-memory and models itself after one of the cultures in the memory bank, as it were. Large, successful colonies mimic well-organized warrior cultures; smaller groups of mants (perhaps scattered during an inter-colony war) will quickly adapt to a culture which suits their new situation. The joint hive-mind of a group of ants is quite skilled in assimilation of technological ideas and in the rapid dominance or domestication of other animals.
Encounters with a mant colony should use the following table to determine their character.
1 - Zulu style. The mants carry large shields of sawgrass woven with chitin, and wield spears.
2 - Greek. Mants wear extra armor, crested helmets, and fight with spears, round shields, and swords. They insist on calling their hive a 'polis'.
3 - Centurions. Each mant is identically dressed, clad in crested helms and capes and the like; they wield javelins, sword, spear, and shield. 25% possibility they've invented to-scale ballistae or the like.
4 - Feudal knights, or Samurai. Warrior-mants are armored, and many of them ride steeds - huge spiders, rats, beetles, prairie dogs, whatever's available. Each mant has its own colorful livery; they are armed with sword, shield, lance. May be supported by large groups of archers. Will use tiny siege machinery when attacking another colony.
5 - Savage barbarians. These mants carry all manner of clubs and spiky weapons, and clothe themselves in the flesh of their enemies and other creatures. Their leader is a sorceror-queen (magic-user of level 1d4).
6 - Air Force. The mants wear identical (unarmored) uniforms, but have tamed flying-beasts of appropriate size (large/huge wasps/bees, stirges, sparrows, whatever) and use them as a dedicated air force, strapping tiny bombs to them, etc.
7 - Elf style. The mants wield bows and swords, try to protect vegetation, and frolic. Easily distracted by poetry.
8 - Dwarf style. Most of the myrmida wear false beards woven of plant material and spend their days digging deeper and deeper for precious stones and gold.
(Obviously any warrior/military vibe can be used to create different colonies of myrmida - Scottish Highlanders, Gurkha, snake-eating Special Ops, etc. A mant encounter is an opportunity to ham it up.)
Encounters with roaming mants may use this table instead.
1 - Robin Hood and his Merry Mants. These myrmida, clad in grasses, fancy themselves outlaws and will attempt to steal from 'the rich' (ie, anyone).
2 - Dirty Dozen - Mants on a mission! The team leader chomps on a tiny cigar.
3 - Grail-questing knights (see Feudal above)
4 - Monster-slaying Argonaut mants (see Greek above), determined to kill something much larger than themselves (a buffalo, a crocodile, the PCs...)
(There's also the possibility that the PCs could encounter a mant colony which is later destroyed; a ragtag bunch of survivors then model themselves after the PCs...)
Although the mants tend to be warlike, they are not necessarily hostile; in fact, some groups of mants are particularly receptive to whatever mood the 'intruders' happen to be in at the time. Parties approaching a mant colony intending to trade may indeed find ant-merchants sallying forth to meet them. Some individual mants are hypersensitive to the needs and wants of humans around them. Myrmida colonies which remain in close contact with a human settlement will begin to take on cultural and linguistic quirks of that settlement, as the hivemind 'absorbs' the cultural mores.
"I don't camp near an obvious mant-hill no more. Not since the time I woke up and found three little ant-guys dressed like saloon girls standin' on my chest, singin' ta me. Them things get into yer head, I'm tellin' ya."