Complex sentence: Their mutated "bodies" are revealed to be the missing brains and connected spinal cords taken from their victims; the spinal cords have become very flexible and also sprouted feelers, and each brain has developed a pair of small eyes on extended eye stalks.
Split into simpler sentences: Their mutated "bodies" are revealed to be the missing brains and connected spinal cords taken from their victims; the spinal cords have become very flexible and also sprouted feelers. Further, each brain has developed a pair of small eyes on extended eye stalks.