Odin (The Girl Who Died)

"Odin" was a general of a species called the Mire, one of the biggest warrior races in the galaxy.

Biography
He took upon himself a hologram projection to appear human and adopted the name of Odin to trick Viking villagers by choosing them for the halls of Valhalla, in fact a place to kill them, to feed off of them.

He appeared in a cloud to the Viking villagers by use of a hologram, telling them to send their best warriors to dine with him in Valhalla. When his henchmen were sent down, they selected the strongest warriors and brought them up to their spaceship, where they were all killed except for Ashildr and Clara Oswald, who had brought half of the sonic sunglasses with them. Foolishly, Ashildr declared war on the Mire for what they had done with the village's warriors. "Odin" told them he would send ten of his warriors down to the ground in exactly twenty-four hours to fight the village's best warriors. He beamed them back to the ground, where Ashildr informed the villagers of their impending doom.

Later, "Odin" himself went down to the village, accompanied by ten Mire. He is greeted by a party, thrown by the Twelfth Doctor for their upcoming victory. "Odin" threatens to open fire on the unarmed citizens of the village, and that is when the Doctor signals Einarr to start an electric charge through some electric eels, which pulled the Mire soldiers' helmets to a magnet, resulting in their true faces being revealed. Then, after Ashildr was given a Mire helmet, she projected the image of a sea dragon to scare off the Mire. The warriors retreated to their ship, and "Odin" faced the Doctor, who threatened to upload a video of their defeat to the Galactic Hub. Furious, "Odin" teleported back to the ship and left Earth. (TV: The Girl Who Died)