The Master Healing

[aquagorillabear]

I've been trying to beat The Master for... oh, about the last hour and a half. Very frustrating.
I thought I had read that, despite his difficulty, one great thing about the fight is that he can't heal, so eventually you should be able to whittle him down.
Well... I whittled him down many times, down to 50% -- and then he heals to 75% -- down to 25% -- then he heals to 50% -- down to 3%!! -- then he heals to 25%.

So, finally, I give up and start looking for advice, and every post I read says something like "but he doesn't heal, so you can do it!!! Hang in there!"
Um...
What's going on here??

[Tradewind_Rider]

Hi the Master is a necromancer.

It does not have Consue Soul as a fixed, but it can have the talent from his class.
So, it cannot always heal, but he has a chance to have a nice healing talent.