Yes, so Rustbits are a tradeable counterparty asset on the blockchain, they are also used in the game (SP:Age of Rust) and act as a premium current in the game. It will be able to be earned as a reward by solving game challenges and puzzles, tipped from other players, dropped when killed, and picked up by other lucky players, etc.  Rustbits can also be used to purchase blockchain cards which you can trade, collect, or use in the game. The game is free to play, so you don't need rustbits to play the game.  At the end of the token sale, all the unsold rustbits that are in the ICO pool will be burnt.