Have you ever flown over a coastline and looked down at the very edge where land meets the ocean? Waves come and go, steered by the wind, they crash against the cliffs and wash against the shore with light splashing sounds, they carry life within them, they rise and they fall in an eternal circle.
But from above, all you can see is a perfect line, soundless and smooth like the rim of a wine glass. You cannot hear the waves lapping on the shore and giving rise to a delicate murmur, like bubbles fizzing ever so quietly. You cannot see the sand whirling in and out of the ebb and flow, waltzing in the water. Life is seething at the edge of the ocean, but you see neither details nor motion. Just a clear contour. An illusion.
Come closer, lean in, and you will see a battlefront.