I've been playing a Promethean mage recently, and something struck me as odd when casting fireball. I'd get blood sprays in areas that didn't seem to make sense. Got some screenshots to illustrate: Before: http://img21.imageshack.us/img21/5320/2011080600001p.jpg After: http://img688.imageshack.us/img688/2056/2011080600002.jpg And a second one... Before: http://img89.imageshack.us/img89/9318/2011080600003.jpg After: http://img20.imageshack.us/img20/356/2011080600004.jpg What you are looking for are the blood sprays *behind* me. I'm never touched, none of the enemies even get close to me, but I still end up surrounded by blood. Not sure if this happens with other spells as well (AoE or otherwise).
The obvious answer is that the Obvious Fireball is so obviously powerful that the blood flies for many feet in random directions. Obviously.
Ah, that's Blood Magic in operation? Interesting, I didn't realize there was a visual effect like that for it. In that case, "bug" solved.