كَأَنَّ مُثَارَ النَّقْعِ فَوْقَ رُؤُوسِنَا وَأَسْيَافَنَا لَيْلٌ تَهَاوَى كَوَاكِبُهُ
Dust rising above our heads and the swords resemble a night with falling stars.
The point is the integrated appearance of darkness punctuated by moving flashes, not merely separate comparisons of dust and swords. The shared aspect arises from the composite configuration.
Treating every constituent as an isolated simile misses the organizing scene.