User blog comment:IamJakuhoRaikoben/Chapter 355: Song of the Fairies, Review./@comment-6299840-20131011225313/@comment-5580383-20131015012448

Well Lyon didn't stab the heart of Gray and no one said no one attempted to kill in this series, besides Lyon has nothing to do with Erza.

Which is to my point about Erza not killing anyone. Haku is a skilled user of needles and even hit Naruto and Sasuke within vital areas and neither of them died

Yeah but the mages she hit are easily alot tougher than novice ninjas at their weakest so i don't see how novice Erza with no control of her weapons would be able to actually kill them or do fatal damage, also some of the eitle mages appeared to be armored as well so it would  do serious injury but likely no fatal  damage.

http://www.mangapanda.com/135-7196-11/fairy-tail/chapter-81.html

Also her having no skills or having a calm mind makes it less likely that those swords accurately did fatal damage,especially given the guys she took out were etile mages of the tower who appeared to be armored.