...or after the "Is it a bird? Is it a plane? No, it's the SUPERBOX!" notification.
Then you get various rewards, as: 1000 crystals, 50000 crystals, a minute of immortality, or 48 hours of premium account. That gold box is dropped only during the April Fools event (1st April)
I think a gold box shold be rised 50 crystals for every rank you level up starting at warrant officer 1
and they should change the 1000 crystal sign to ???
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