Air Dome

[Micah]

The additional gem domes don't break, so you only need one in a prov, I don't see any imbalances. If you want to burn 50 gems per province stacking up multiple air domes I think you've pretty much already lost that battle, especially since a spell still has a 20% chance of getting through since only one dome is actually checked, so it doesn't make you any more resistant to the heavy artillery spells (flames from the sky and murdering winter) than a single dome would.