The above is for phase 2 missions. The only one I remember for phase 1:
level 80 (500+8x70)/80 = 13.25 per stamina

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Originally Posted by maotd

2nd phase unlockable stage give you 700 curreny while 1st phase's one give you 345. So, you will get 10 more currency on 2nd phase's one.
If you're able to do the 10 fireflies stage three time, it is far better (you will get 2070 currency for 2 fireflies where the phase 2 unlockable give 1400 for the same amout of fireflies). If not, prefer the 20 fireflies stage. 10 currency is always 10 currency.
And yes, bonus stages are useless since they don't give any fireflies or life crystals.

Ah, I forgot the 1st phase summon only gives 345. That would make each guiding firefly worth 69 currency.

Is it possible to do the summon 3 times? By the time I finish the first round, I only have 10-15 seconds left to start the 2nd round. Do you have a way to skip the rewards screen or something?