Maybe Mitosis a Firefly then. The 3
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for a 4|2 creature is better than 7
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for a 3|7 creature, even if the child can't continue spawning stuff. Also speeds up the rush, since you're more likely to have 3
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on the end of a turn than 7
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.
Second turn play FFQ, third turn spawn a Firefly and Mitosis it. Fourth turn spawn two more Fireflies.