Gwrgi Garwlwyd; "Man Dog Rough Grey" is a murderous warrior in Welsh literature. He made a corpse of a Briton every day and two on Saturday so as not to have to kill on a Sunday. He was ultimately assassinated by the hero Diffydell mab Dysgyfdawd, which was recorded in the Welsh Triads as one of the "Three Fortunate Assassinations". Garwlwyd also appears in the early Arthurian poem Pa Gwr yw y Porthwr, in which he is described as having fought in the Battle of Tryfrwyd against the Arthurian heroes Bedwyr and Manawydan.
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Gwrgi Garwlwyd Wikipedia(Text) CC BY-SA