thats true for mid to late game, or maybe real mono-fire decks, but in rainbows or decks with not many burning pillars/towers, and at starting phase, they are nearly equal.
i also would prefer a change to dual-color (like
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or
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to "pump"), and a bit better initial stats.
in mono decks, you have a lots of counterproductive synergies, like farenheit and bolts (or high-cost dragons), so quantum-eating spirits are not the best choice, and for rainbows most of the time golem is far better.
i would really like to see a small buff of upgraded version, like 2/4-stats or 1/3 with 2
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cost, to make it more frequently used.