Tetrahedra: Angels of the Tessellated Realm

They are beings of pure Order, hailing from a distant plane in which their bodies tessellate endlessly together. In our world they appear as three-side pyramids hovering in space, fringed with cold fire. Each one surrounded by four smaller pyramids, which in turn are surrounded by yet smaller pyramids, and so on. In the centre of each pyramid is a glowing eye.

 An aura around them forces everything to tessellate with them on every scale. Get too close and you will begin to cough blood as your organs, cells, molecules and particles all try to arrange themselves along a triangular grid.

When threatened they will shrink down to microscopic size. When numerous, they will fuse together into giant pyramids that dominate the sky.


THEIR CULTS

Cultists worship the Tessellated Ones in secret. They infiltrate cities and slowly restructure them according to the divine pattern. First a few geometric sigils, carved at certain key points on the landscape. Palindromic code words whispered from balconies at midnight. Plot the locations of their signs on a map and you will see they are forming a vast overlay of Sierpinski triangles. Another sign is the lowering of local entropy - coin flips start to come in regular patterns of threes.

As Order descends upon the city, the streets themselves subtly realign into tessellating patterns, while the inhabitants' thoughts begin to run on tracks. At last the ground is prepared for the incursion of the Tessellated Ones into our universe.

They come and they dominate us and they make everything run on triangles. Eventually the incursion site becomes a giant hive of tessellated matter - tetrahedral bodies interlocked with octahedral voids. Human bodies are twisted like bound feet until they fit the pattern.

The incursion is just a beach head. Slowly it will spread, until our whole universe is just like their own.

THE REVERSE INCURSIONS

Or will it?


Certain heretical splinters of the Tetrahedra-Cults tell a different story. They tell how, just as the Angels can enter into our world, we can step through into theirs. How certain cultists travelled there long ago and learned to subsist in the spaces between the triangles. How even now they dwell in the infinite plane, spreading like a rot, undermining the perfect pattern.

There are whole towns in that other world, dimensional pirates who use the triangles to raid various parallel planes in search of food and supplies. They have hollowed out vast pyramid-caverns and dressed them with the spoils of worlds.

Because of them, the pattern is slowly collapsing. Vast quakes echo through the plane. Dislocated walls of tetrahedra grind against each other. In their own realm they are powerless to respond to these colonists, as to do so would require them to leave their pattern. Thus their only hope is to seize our own world. Their incursions are not a mission of conquest, but a last desperate attempt at escape.