Spell Costs Increased?

[incognito]

I'm trying to figure out why the spell costs for murdering winter, flames from the sky, and some other long range bombardment spells increased so substantially from DomII. In my experience, these spells were already expensive and tended to be only moderately effective versus many troop types. Moreover, with early age races having very high hp on their troops, the damage from these spells can seem even more inconsequential than normal. Is this a bug? Was the spell effectiveness increased? Given these cost increases, what long range bombardment spells have become people's favorites in practice?

[Taqwus]

Both Murdering Winter and Flames from the Sky scale with the size of the target army rather instead of flinging a number of effects that depends only on the caster, so perhaps it was thought that their costs should grow just as army sizes have.

[PvK]

Ya, they're not moderately effective against a huge army which isn't immune to their effects - they're devastating, make it too risky to mass huge armies when someone can cast them, and give the caster an insane amount of experience.