Michael Moorcock (haha “more cock”) is a British author of science fiction and fantasy literature, most prominent for his "weird fiction" focus; the high-magic Sword & Sorcery "Eternal Champion" universe, most iconic for the subsetting focused on Elric of Melnibone, is the most notorious of his many, many works.
So why is he here? Because he invented a lot of stuff seen throughout /tg/! Moorcock's Eternal Champion cosmology directly inspired both the Alignment system of Dungeons & Dragons and the Chaos Gods of Warhammer Fantasy and Warhammer 40,000, with the [eight-pointed star] of Chaos lifted directly from the Eternal Champion universe with almost no changes. In addition, Elric's cursed sword Stormbringer inspired the Dungeons & Dragons artifact called Blackrazor (and Warcraft's Frostmourne for the /v/irgins) while Elric himself has influenced many characters, such as Warhammer Fantasy's Tyrion and Malus Darkblade.
Usually Moorcock has been cool with other fantasy authors lifting his work. After all he's credited influences of his own: Elric himself is Kullervo the Finn set in a Robert Howard setting. Although /b/ cucks will assume not even skin deep similarities/counters (like Elric himself is to Conan)to be plagiarism, notably with the, thanks to CDPR & /vg/, more successful Witcher series.