All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His Slave and Messenger.
The view adopted on Islamweb is that it is permissible to play electronic games in principle as long as they are free of violations of the Sharee‘ah, such as that they do not distract from the remembrance of Allaah and obligatory acts of worship, do not involve gambling, prohibited music, images of women exposing their 'Awrah (body parts that should be covered) and do not lead to enmity and hatred among the players. Please, refer to Fataawa 86146 and 91906.
As for the game you mentioned, it is difficult to make a judgment about it because we are not fully aware of all its details. However, in general, selling and buying in-game items and features, such as buying players, is permissible as long as the game itself is permissible. Those in-game items are sources of utility inside the games and they may be used in trade. This is not in and of itself considered the prohibited gambling.
You should know that the gambling that is prohibited is that which involves taking a risk between two players over real (and not virtual) compensation. One pays money and could win or lose. The Kuwaiti Encyclopedia of Islamic Jurisprudence reads, "The jurists arrived at a scholarly consensus on the prohibition of a game that involves gambling. The Shaafiʻis held that if money was stipulated from both sides so that the money would be for the winner of either of them, then this is forbidden gambling. They underlined that in this case it is a major sin."
Now that you know the criterion for prohibited gambling, you can judge whether this game or any other one is prohibited.
Allaah Knows best.