Is it permissible to organize a tournament with an entry fee in virtual currency within an electronic game (not real but convertible into real money), with prizes for the top three places that are not affected by the entry fees?

If a player pays money to win a prize, this is forbidden gambling, whether the payment is with real or virtual money, because the prizes come from the total subscriptions of the players and most of the subscribers lose what they paid.

A Muslim must not cause people to waste their time, money, and efforts on games that have no benefit, especially virtual games. The Prophet, peace and blessings be upon him, commanded us to preserve time and occupy it with what benefits us in this world and the hereafter, saying: "Two blessings in which many people are deceived: health and free time." A Muslim will be questioned on the Day of Judgment about his life and youth and what he spent them on.

Amusement is not forbidden, but it must be regulated by Islamic Sharia (definition) guidelines.