And the different effect depending on target is there too: the light heal will damage death or darkness creatures.
Also nice concept, and I like the balance of making it a neutral (other) card.
Maybe you could make it have one of three effects, depending on your quantum pools (to reflect the notion of balance between yin and yang)
1. Generate 1
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and 1
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when you have the same size
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and
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pools
2. Heal yourself for one amount when you have more
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3. Damage the enemy for an amount when you have more
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That way you would have to play cards costing
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and
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in order to tip the balance from one to the other, and if you find balance, this will grant you power (but using that power will unbalance again). My only worry is card space and description size.