User blog comment:FairyRaven/One-time-only Spells/@comment-904888-20120709005643/@comment-4829046-20120709125912

That's what I said here "The first time Makarov cast it, he considered the Shades to be true enemies so they were killed but he didn't consider the Phantom Lord mages as real enemies. He only used it to teach Jose a lesson." He didn't hold the other mages in such regard to actually KILL them. He only wanted to defeat Jose and show the power of Fairy Tail. And the shades did disappear because of the Law.