DnD Music - The Shadowfell / Mysterious / Dark Ambience - Wandering in the Shadows

While my players had their adventure in the Feywild, an other group, playing parallel to mine with another DM and good friend of mine, went to the Shadowfell... They told us about this dark, mysterious and treacherous place where they found a revolver, possessed by an ancient spirit. She accompanied the adventurers as the weapon of the hexblade warlock and with each killed creature, she became stronger and stronger... What could go wrong?