I was wondering why fire is such a nice choice to win easily and quickly.
Each card in the fire element is nicely done, none are overpowered.
But fire has a response to everything :
* Nice and quick and cheap permanent control : Deflagration
* 5/6 dmg to creatures : Rage potion
* Control of a many creatures : Rain of fire
* Control of immortal creature : Fire Shield
* Growing creatures : Lava Golem/Fire Spirit
* Resistant creatures : Phoenix
* Direct Damage / Large amount : Fire bolt
* Large damage weapon : Farenheit
* Need more mana ! = Immolation
The only other element with all that things is Entropy, but it is much more slower and random.
Fire is quick and predictable. It's just boring. The lack of heal is no problem, as your opponent has no time
to strick back, most of the time.
So either remove some things from fire (like "deflagration" could become light
"break", would be a MUCH more balanced game !),
or perhaps add some weakness to fire (it's not what I prefer) :
* Frozen and flooded fire creatures die immediatly
* When kids play with fire, they always got burn, perhaps lose some life when you play rain of fire/fire bolt
* pay life to revive a phoenix
* add "anti-fire" cards ( ??? )