Both K- and I have noticed problems with Mind Flay missing (a lot!) lately, most notably when I wtfpwned his ass while dueling our SPs. There are numerous threads about this on both official and unofficial forums, along with confirmation today that the devs are aware of the issue (no confirmation, sadly, that it's going to be fixed).
Mind Flay Bugged?
November 3, 2008 by Khaeli