How do I use Armageddon's Blade?

Why, even if it's not ideal... Armageddon makes sense to cast with a leveled-up Fire Lord. And if your own units retain their original defense while the enemy's defense is halved, that's a significant advantage... Of course, there isn't a faction that specializes in both Light and Chaos simultaneously, so a Knight casting Armageddon is quite an exotic sight.