Listen to the sound clip Monsterbirds 7 from Nightmare SFX Library: Monsterbirds 7 Monsterbirds 7 This sound is from Nightmare SFX Library The Nightmare S Library is filled with an array of sinister sounds that will send shivers down your spine. The first sound, "Possessionvector3," emits an eerie electronic hum that seems to beckon to you from the depths of the darkness… Go to the full soundboardwith more sound clips Search