Box  gacha  is a virtual box of set items with known probabilities. Its popularity grew around the time that the complete  gacha  controversy was becoming publicized. As items are pulled from the box, the likelihood of receiving the desired item increases since there are fewer items in the box. [12]  It is also possible to pull every item in the box, provided the player is willing to spend enough. For this reason, some players will calculate how much money it would take to ensure they pull the item of their choosing. [13]