I just played my 2nd game with Stormwall against Circle.
Basically the Circle player took Kaya and pretty much upkept the spell that gives Stealth to her Battlegroup (Wolves).
So the Stormwall was rendered useless in range and was only able to attack when things got up close and personal.
Obviously I'll have to bring Stormwall with a caster that can mitigate Stealth.
so in this situation all I can do are the following:
Plant the Lightning Pod to a location where I can zap the Stealth units and bring the Stormcallers. (Although practically useless against beasts and jacks - POW 10)
Get Stormwall really close and tie up the Stealth units/beasts/jacks and then use my other jacks to assassinate the enemy warlock/warcaster.
Anyway, it only shows that PP did a good job keeping the arms race balanced... you don't really need a Colossal to win.