Such a game is really BT. (Note: "BT" in this context might be better translated to "overpowered" or "unfairly strong" if referring to game mechanics or characters. If "BT" is intended as a casual slang, it could stay as "BT" depending on the audience's familiarity with the term.) A more natural translation might be: "This game is so overpowered/unfairly strong."