I don't know the game, is this one?
It doesn't seems multiplayer. You have to explain how the multiplayer works.
From your Twitter the only thing I have found (without going too much deep into it) is that the game is a TCG.
But you can do a TCG in different ways:
- Local multiplayer (2+ players) and 1 PC
- Local multiplayer using the same network (each player has their own PC)
- Online multiplayer peer to peer
- Online multiplayer with server
Plus you have to specify if it's turn based or real time.
Depending what you want to do the development is different as well as the costs.