The first two enemy waves are surprisingly easy. The undead are slow and don't attack very often. Just go around taking them out one at a time and give your will meter a chance to build back up.
In the last two waves there will be a good deal of higher level undead. These enemies block regularly and attack more often than the lower level ones. Use an unblockable flourish attack, or Enflame or Force Push if you have a few enemies around you, or use Slow Time to slow then down even more.
At the end of the round you'll be asked if you want to continue or go back to the cells. Choose to continue unless you're in desperate need of healing items. -- cut-scene --
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