The WoL are the agents of Hydaelyn, the Ascians are the agents of Zodiark. Just as there are numbers in the Ascians such as Elidibus who realize that there must be a balance between light and dark, so too does the WoD and soon the WoL. Both Ascians and WoL can bring a world to ruin through an extreme of light or dark.

It's far more likely that Zodiark is fairly reasonable in person just like Hydaelyn is, but the Ascians take his will too far and wish to establish their patron deity's utter dominance, just as the WoL does until they learn of the truth from the WoD.