Ramapithecus, the Tuatha's apes
Ramapithecus: the red-coated apes the Tuatha Dé Danann keep as servants, carrying their water and baskets, held by crystal and song alone.
Who they are
Round every Tuatha camp and city there are apes. They are heavy, red-brown and quiet, a little smaller than a person, and they walk on all fours on the flats of their hands. They can stand up for a moment to set something down, then drop back onto their palms. The faces are long and dished, with a deep jaw and close-set eyes. The big males show the tips of their canines.
The exiles call them Ramapithecus, after an old museum name for apes very like them. Nobody in the camp has ever seen one living wild. Wherever they came from, the only ones left are the ones the Tuatha keep.
What they do
They carry. A male takes a lidded basket strapped high on his back, a female two water skins, and the young ones follow their mothers with nothing at all. They fetch water from the streams, haul fruit and fodder up to the halls and set it out on the tables. Each wears a girth of pale cord behind the forelimbs, strung with a few beads of stained glass and clear crystal, and nothing else.
How the Tuatha hold them
There is no chain and no collar on any of them. The Tuatha have never needed one. A keeper hums to a shard of tuned glass, and the troop goes where the note goes. The apes are reared to the song from birth: the beads on a young one's cord are its first notes, and a new bead goes on as it learns another. An ape that has heard the song all its life doesn't wander from it.
On the battlefield
They are living scenery, like the wild animals of the period. A small troop works just past the edge of the board round a Tuatha place: an old male, a female or two, often a young one. They never touch the rules. They give no cover, block no sight line and nobody can target them. When a unit you can see comes close, the troop moves off along the edge. They never react to a hidden enemy, so they never give one away.
They don't fight for the Tuatha, and the exiles don't fight them.