[WarBringer]

I cannot find a quote at the moment, but off the top of my head I believe Gandalf stated that NOT EVEN Glorfindel and Aragorn could withstand the Ringwraiths, which would be a testament to their power. Beyond that, it is simply known that Glorfindel was reincarnated and resided in Rivendell.

Another possible defense to a warg charge would simply be to gain higher ground, thereby lowering the effect of the added height given by a warg, and giving the defenders time to strike before the wargs could.