I'm frankly ashamed that I've only just recently learned about the Battle of Blythe Road, an actual real-life magical duel between WB Yeats and Aleister Crowley that ended triumphantly when Yeats dropped the magic act and just kicked Crowley down the stairs.
As future Yeats biographer Richard Ellman explained in a 1948 edition of the Partisan Review, Crowley and Yeats were part of a secret order called the Hermetic Students of the Golden Dawn, along with some other folks you may have heard of like Bram Stoker and Algernon Blackwood. This esoteric posse shared an interest in magic and the occult — but Yeats was concerned (perhaps even legitimately!) that Crowley might abuse their arcane knowledge for evil ends. So they tried to banish him from the group's inner circle.
Needless to say, Crowley was not pleased. From Ellman:
Crowley refused to accept their decision. He went to Paris, and there persuaded the chief of the Golden Dan, a Celtophile magician named MacGregor Mathers, to deputize him to wrest control of the London temple of the order away from Yeats and his friends. Mathers furnished Crowley with appropriate charms and exorcisms to use against recalcitrant members, and instructed him to wear Celtic dress. Equipped accordingly in Highlander's tartan, with a black Crusader's cross on his breast, with a dirk at his side and a skindoo at his knee. Making the sign of the pentacle inverted and shouting menaces at the adepts, Crowley climbed the stairs. But Yeats and two other magicians came resolutely forward to meet him, ready to protect the holy place at any cost. When Crowley came within range the forces of good struck out with their feet and kicked him downstairs.
Crowley retreated to lick his wounds, and later tried to seduce the Anglo-Irish artist Althea Gyles into aiding his revenge. But Gyles was a clever one: she stole a lock of Crowley's hair and passed it on to Yeats, who allegedly used it to cast a series of spells that would limit Crowley's power.
This last part may or may not have involved a vampire, in Ellman's recollection? Unclear. Anyway there's a short documentary above if you want to learn more.