When you get a Mystery Gift, you can increase the amount with a multiplier.

Each of the 7 cards has a hidden multiplier, 1x-7x. Keep choosing increasing cards and they will add together to reach the final multiplier.

Choosing cards ends when you choose one that is less than your previous multiplier (in which case, the final card is not counted) or when you find the 7x card (which would guarantee that the next card would be less).

Some examples using bonuses picked in the following orders:

1x, 6x, 5x = final multiplier of 7x (1 + 6, the 5 was discarded because it is less than 6)

2x, 5x, 7x = final multiplier of 14x ( 2 + 5 + 7, choosing ends automatically after 7)