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The Linéals, one-dimensional entities, conceived of the existence of only an infinite line. The Planes, two-dimensional creatures, inhabited a two-dimensional world without depth.
One day, a dimensional anomaly generated a point of intersection where these realities collided.
The Linéals, limited to a single axis, perceived only tiny dots appearing and disappearing in their one-dimensional universe: the cross-sections of the Planes as they crossed their line.
Meanwhile, the Planes saw only lines that suddenly emerged on their plane of existence, then blurred: the slices of a passing three-dimensional being that had intersected them.
Both races watched these manifestations with awe, unable to comprehend the terrible dimensional fragments that each worldview perceived.
What they did not know was that soon a new order of creatures, the Three Dimensional Ones, would come to unify and transcend this cosmic divide between their parallel realities.