First of all: awesome card and mechanic!
On balance: as ak65ala said, flying weapon + fractal let you have (effectively) a rechargeable spell.
Lightning costs 2
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|1
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and deals 5 damage.
This costs 3
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|2
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and deals 6 damage, but it's rechargeable.
A single fractal with an empty hand will generate 8 x Kamikaze.
Damage when replaced | Unupped x 8 | Upped x 8 |
6 | 48 + 4 damage for 24  | 48 + 4 damage for 16 . |
5 | 40 + 4 damage for 24  | 40 + 4 damage for 16 . |
4 | 32 + 4 damage for 24  | 32 + 4 damage for 16 . |
I think that unupped should be:
3
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- Weapon: Deals 4 damage at the end of every turn. Deals 4 damage to your opponent when replaced or destroyed.
and the upped:
3
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- Weapon: Deals 5 damage at the end of every turn. Deals 5 damage to your opponent when replaced or destroyed.
Notice that the cost is the same, but the damage is raised.
At least you will need 2 fractals (for the upped version) and lots of quanta to kill an opponent this way.
Of course this is my opinion.