As part as my job as a Game Designer, I have to tune game modes and manage the distribution of virtual currency to players. I developped a tool for a Hearthstone Arena like game mode, which allows to tune up different values like the entry fee, the number of lives and the number of steps. Then it launches a simulation that will calculate the gifts to the players, depending on the difficulty on the inputs. This tool is very useful to fine tune the economic of a multiplayer game.