HA ha first rate
Inferno thing... well, the name does not sound fitting, that's for sure. As for what the thing does... yes, it does sound much like Fire, and it'd be useful to make the enemies more vulnerable for your Fire Bolts. You might want to make it drain 3 max HP per turn up to 15 drained and the upgrade could have a 5 per turn drain rate.
Playing all six makes both players fall to 10, but then it's not really doable as against Fire on one side both sides do high damage, with Fire's hope being outdamaging the enemy, so you'd die before having a chance.
Iceberg also doesn't sound fitting, being... an object... I'd assign some temperature change things to both names. As for what it does, it does seem pretty balanced with that cost, especially when you mention Ice Shield that provides free freezing. Without it, I'd suggest lowering the cost, but it exists.
It shouldn't include Stasis as it isn't Freezing.