Off topic:
Card combos are important to consider when balancing a card.
Powerful combos (blessing + otyugh) do not invalidate a card.
Overpowered combos would require modification to a card.
On topic:
Shield is a disadvantage.
Fire shield would be worth more than 6
|4
if it were not a shield.
Fire field's damage aspect is better than a non shield Fire Shield.
Fire field is better than just Fire field's damage aspect
How much is mass fire regeneration 1 worth?
Well it would be combined with rage potions, liquid poison and would slow down CC. That is worth at least 3 quanta (underestimating).
So Fire field's balanced cost > Fire field's damage aspect > non shield Fire shield > Fire shield [6
|4
]
As a net underestimate I would recommend 12
|10
minimum.
However I do not see Fire as an element where creature healing not to mention creature regeneration is appropriate.
Light is the creature healing element.
