The best are the Archpriests of Erathia, thanks to their magic resistance, the Erathia symbol, multi-tile attack, HP, and huge mana pool. The Fire Wall spell is also great, and even better are the Guardians of Erathia, especially when things get tough. After death, they will deal damage to enemies around them. Unicorns are also pretty good.
As far as I understand, they also have the Fire Sign ability? Yes, I completely forgot about them. They are one of the strongest creatures for their level.
So you fall at his feet hes the one who betrays you
Its the servants devotion for the decay
Stand up
There are no flowers on your grave
There are no chains
There I keep chanting for the forgotten name © Amorphis