Summon your creature. (I'm sure you do) Make sure that Sassan is healing you (if you are a melee). If you are a ranged/ magic user then have her summon as many as possible (CHOICES she gives you before the fight).
Concentrate on ONE of the 2, Either LAIKEN or ONLY RAKAZEL. When one dies the other will as well. Other then that all I can say is pot like crazy and don't stop moving.
(I used a mage on one of the playthroughs I did and it didn't last longer then a minute.
Hope I was of some help.