Stiyl Magnus (ステイル＝マグヌス Suteiru Magunusu?) is a magician affiliated with Necessarius and was Index's partner, together with Kanzaki Kaori, two years prior to the start of Toaru Majutsu no Index.
A formidable magician who uses runes and fire magic, he was the first magician and antagonist that Kamijou Touma faced in the series.