Idea gained from looking at my garden lawn
A war conflict on an epic scale, fought between city states, great wizards towers and strange underground races, with the occasional interruption of gargantuan kaiju-dragons and inexplicable chthonic entities
Aesthetic would be Elrics Melinbone in fineness but in colour and form, more like 19th century and later Fairy images - very bright, summery, decadent. A high-toned luxurious and sensual society of nobles, plus Warhammer, plus Honey I Shrunk the Kids
its a Wizards garden and the PCs are hired to sort out its infestation problem before summer ends, this means they get shrunk to micro-scale, and that leads to this ballardian dreamscape ruined plant arcology where grains of soil are like small hills, daisies are forts and daffodils are huge city-states
Fae queens riding flitterflies, flea-cavalry, infantry slogging through nightmare three-dimensional mazes being hunted by centipedes, war without end as the apex culture of a race of fae sorcerers blast each other with desolating magics and entrap each other in schemes - high intensity warfare and court drama with the PCs mixed up in the middle of it all.
From 'Warframe'
THE GREEN TOWERS
War in a cool green cathedral shaped by vast leaves like towers of glass. A sylph queen garbed in armour of plated butterfly scales gazes down as an army musters outside her gates. The armour of a green knight expands into a chrysalis - what emerges is a sorcerer. Winter isn't just a season but the end of the world, and the rule of worms.
What is the sun but a green-gold glow that fills the air and in sliver gaps between towers, a blazing radiance which scorches and destroys.
What is night but a black riot of sounds, the grumbling of worms in the earth and the squealing of moths as they pass far above? What is a dragon but a being so vast its claw can crush the towers of the highest mage, armoured in great sweeps of scales themselves larger than many cities, a spear so mighty that it can plunge deep into the earth, deeper than the deepest mine, and pull forth entire, one of the great worms, and carry it off into the sky. A war of gods and monsters.
INVESTIGATION
A world at this small, very small, microverse, would need more actual research than is customarily assumed. The classic post-fairy-tale paracosms, Honey I Shrunk the Kids, the Marvel and DC shrinking heroes etc, tend to work at a scale at which the very small to us becomes very big to them (Godzilla battles a single rat in the New York sewers etc), but at this very micro microverse, what is small to us becomes nearly insensible to them. A thrush, not just a monster but a Behemoth of god, and what is nearly microscopically indistinguishable to us becomes the material of life to them.
How does reality work at this scale and how much blurring into dreamland should we engage in?
Gravity and oxygen for a start, will be very different. For a being this small climbing would not be hard.
What are they breathing? Are they breathing like we do or are they fundamentally different beings only seemingly related to our world, like parallel reality creatures existing at this low scale? Like ghosts or the flickering spirts of dreams sparking into corporeality for one long summer.
And I would need to look into the substances of the microverse, at the scale at which an ant is like a giant war elephant or something, what is a sword made of? What are people drinking? Are they burrowing into the surface tension of water droplets like miners with asteroids?
Are you chilling with a tardigrade? Do you snort RNA like its a drug?
If I remember my microverse properly, its a realm of scent as much as sight. The wind doesn't even reach down here, fogs and clouds of pheromones drift opalescent through the still air, to us it would be like a second texture to the air itself, tinting and ruffling, though not necessarily obscuring. Pollen whirling through the air like cartwheels. A poisoned blade drawn from the stinger of a nettle.
The land of the dead cannot be very far away, its down where the roots go, beneath the stones. The land is not level, it is built up of great jagged boulders of soil, each one independently alive, and there are cracks between them always, it only needs a slip and down you go into the lightless depths to be hunted by skittering centipedes. The earth quakes and churns with the movements of the great worms beneath it. A mosquito is a vampire dragon which, every hundred days, feeds upon he blood of great forgotten gods.
Richard Dadd
THE WARS OF THE PETAL-DWELLERS
The armies of the petal-dwellers marching forth in great crumbling lines, shining like droplets holding high banners made from the tuft hairs of baby moles, of single fish scales, blowing strange trumpets carved from the earbones of shrews. Ant-mahouts perfume the air to drag forth huge false-caterpillars; siege engines built from the root tendrils of holly plants. From where will assault come? From above as strike teams ride huge ladybirds in assault? From below as bind sappers tunnel forth under your very feet on the backs of ants? From around as tick-riders encircle the column? Spotters riding preserved dandelion seeds tied to lumbering beetles by spiderweb try to observe but they are little use. A long trek to assault the plant stem of another petal-dwelling lord or lady.
And all for what? A word.. or a glance. A bet or sharp look over the turning of a card made from the dried cornea of a baby mouse. What else is there for a noble to do but to marshal forces and send forth great powers to crawl through leagues of hellish nightmare, rolling dice of crystal quartz* with every turn and pathway, only to assault a green tower, climb its rugose column, hack at its roots, inject troops into its capillaries and in the end a daisy falls in the night, a culture annihilated, its pollen given to the wind and petals fallen to the realm of death to be carried away by pale ants.
(*crystal being maybe the only substance which would look, feel and largely act the same way in the microverse)