Blue Electrical Tentacles are materials in Xenoblade Chronicles X. They can be obtained from Blue Duoguills such as Placid Duoguills located in Primordia's Unicorn Rock and Silent Mire, or Lethal Duoguills in Oblivia's South Coast and Floating Reef. This item can be dropped by successfully destroying one of two tentacle appendages of the Duoguill's head. It is possible to purchase the material for Reward Tickets at the Network Console in the BLADE Barracks. One is needed during A Day in the Life.
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