The power of the spellcasters is undeniable; the holy light tearing through the skeleton swarms, the meteors disrupting the rat infestation, or even the teleportation escaping the siege.
It also depends on the nature of the spells. The Mendicant Monk's mastery of Divine Arts with the holy light is effective against skeletons but feeble against the rat infestation, as he can incinerate a single rat to a husk easily, yet the rat infestation consists of countless rats.
Conversely, Alhazred's spells wrought massive casualties, whether through the crater-inducing meteor or the engulfing dark flame, both more potent than the previous occasions.
It is evident that given enough preparation time, the prowess of spells can significantly enhance.
And coincidentally, Grendel's abilities also counter the rat infestation, simultaneously she has been preparing here for quite some time.
