In another thread i pretty much think we all agreed on that it ONLY deflects
arrows. Cant remember if guided arrow were included, but no spells can be deflected and it dossent reduce the damage of spells either.
i'm pretty sure it can deflect Mephisto's cold orb attack, I think it can deflect missile attacks that have a physical component and spells that are in the form of a bolt. The reason it won't help against fireball is due to splash damage, which is the same for other spells that have splash damage like glacial spike and freezing arrow I believe.
That's probably the most accurate definition we will ever get.
Summerfun, sorry i was phrasing my post wrongly. I actually wanted to put your statement forward as the correct statement and NOT the wrong statement. I am well aware of the fact that the cold ball can be blocked with shields.So did I, but melianor made me doubt it