Pulse

From the game text

When a rock is tossed into a calm lake, ripples are created along the water surface.
Waves that travel in all directions, rhythmic pulses, going far away from our vision range.
But even though our eyes can't see it, these pulses keep moving for an infinite distance,
scattering and mixing with other ripples generated by other elements coming from the most
random spots.
The same happens with sound waves, electromagnetic radiation, visible light...
The truth is that everything does generate pulses through the air, the matter surface, through
time and space, propagated infinitely beyond our mere perception.
Invisible.
Imperceptible.
Everything done by us and those before us travel far into the future.
A silent registry of everything that existed.
For those capable of perceiving the uncountable and confused echoes of millenniums of history,
to track the events that created them is an apparently impossible task.
Humanly impossible.
For that we have machines monitoring the ripples, calculating its expansion and trajectory,
registering each echo traveling through time, letting us walk into the past along the pulse.