The $1 mystery box

The mystery box is in the shop and costs $1 instead of $2. Inside there can be up to 59.7 cookies.

What you get is decided by chance: a big reward drops with a certain chance, smaller ones more often. The winnings go straight to your balance.

The same $1 box is also sold on the Box Game screen. The box you get for winning a Box Game match is a different one: it contains XP, not cookies.