They’ve recruited one of the brighter humans who’d shown a deeper interest in them than usual, to work for them, their plan.
And now, the lichenologist’s work is complete. She’s done everything they had required of her, co-operated in their work, in return for the change to immerse herself in their world.
They are quiet now, passive under her gaze. Their lichenologist.
Crustose, foliose, fructicose - all still, each disc a silent eye. “Good lichen” she says, “Be still when watched, move fast when unobserved. Know your target. Don’t stop till you have enveloped everyone. Who is the master of lichen?” She closes her eyes, holding out her arms. The swarm undulates rapidly over her body, accelerating as she struggles involuntarily. Blocking her eyes, invading her mouth, insinuating into her nostrils, then leaving her, and speeding on through the forest, towards the city.
A hunting pack, insatiable, focused on just one genome.