When Lux uses her E and she tries to detonate it, then dies, she won't be able to use her E for the rest of the game, even after relog, or a death. Then client crashed after i tabbed out of the game. The Lux E spell was shown the spell that made to explode the E, but it was gray, like a passive skill. I have no screenshot since my friend was playing Lux, and was not so annoyed cause of our possible ranked loose, he was not able to take a picture. 
That's exactly what happened to me. I tried to detonate my E and died, and it stopped working. The icon was grey and it says 0 mana cost.
Something like that happened to me, too. I used my E, tried to detonate it and the animation only seemed to be a bright flash instead of the usual expansion of the explosion. Then it got stuck and I couldn't use it again. When I tried to it said: "You cannot cast that spell right now" and hovering my mouse over it showed a cost of [0 mana]. I did not die 'though.
Just happened to me as well! please fix!
