User blog comment:IamJakuhoRaikoben/Chapter 286: Laxus vs. Alexei, Review./@comment-2106167-20120609073032/@comment-4495710-20120609093333

Perhaps Lumen Histoire is a spell that enables the user to use Fairy Law,Fairy Glitter and Fairy Sphere and since Iwan knows about those spells (but he doesn't seem able to use them) he wants Lumen Histoire so that he can use those spells.