[MegaBlues]

When you look at Divine Judgement essentially nullifying most target's defense/resistance for the class' method of offense and Death Knighting as a whole, it doesn't seem so crazy to me. It's powerful, yes, but so are the other invocations. Rather than frontloading the power like Overload, Exgalfa, or Isenshi, the strength comes in the follow-up, and the weakness has to go against the target's innate resistance (Which is most likely not very high, but that's because Ice magic is inferior to Lightning magic and requires a similar stat spread).

Frostbite is an afterthought to me as, again, most characters can simply ignore it (and Cinders are much better both in PvE and PvP).

So I think 5 turns is fair, but 4 as a testing point would be nice too.