Business model: Free-to-play (F2P)
Online computer game, free to use. If desired, the user can top up his account balance and pay on the site to simplify the gaming process. Often, in-game currency is used for in-game purchases, with non-trivial rules for converting from real money (for example, discounts or bonuses for regular users).

Subject of payment:
Any payment made by the user leads to only one final result, this is replenishment of the personal account balance. In the future, the balance can only be used to pay for in-game values.
In the event that payment is made without authorization in the personal account, the user must indicate an in-game nickname. The specified nickname will be credited with the in-game currency "Coin of Luck".