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The Master, under the alias of Frey, influenced the Vanir, a tribe of Vikings in 141 to fight Odin and Thor and the Third Doctor so that he could get Gungnir. The Doctor explained to Jo at the time that Norse mythology probably came from real adventures of early Viking history, as here the fight between Vanir and Odin's folk. (PROSE: The Spear of Destiny)
Thor appears as a card in the Doctor Who: Trump Card Game released in 1978 by Jotastar.
Anthony Hopkins, who plays Odin in the Marvel Thor film series, was considered for Rassilon during the planning stages of the 1990s TV reboot.
Thor, identifiable through his iconic winged helmet and hammer Mjolnir, appears in The Incomplete Death's Head. Although probably intended to be consistent with the Marvel interpretation of the character (who, although the genuine Norse god, becomes a superhero in the present day), he was illustrated with a beard, which his then-current Marvel design lacked.