The only problem I see is that is only balances if you assume your opponent has
quanta, and even then it's a very easy fast kill/one turn kill combo with fractal, since the hunter has such high stats for what he costs to summon.
Fractal hunter = 77 to 88 damage summoned in 1 turn. Would cost between 28 and 32
quanta to summon that many guys.
If you can kill your opponent in 1 or 2 turns with this it really doesn't matter how many of the charcoal hunters they have.
Also, if you have permafrost shield and your opponent doesn't have
quanta then the charcoal hunter would be a useless creature occupying one of your opponents slots.