Correct; she didn't even do any damage. I hit her before she could finish summoning a death knight, so she kept retrying to do that, and never cast Blind or Hell Spikes. I just ran up and started whacking (Stun probably helped then), though you could try Flash Attack if that isn't fast enough.
Variations on the standard Curse / Elemental Hail, Blind / Hell Spikes or scorpion traps should also work.