ROBLOX Cards are cards with codes to either get more ROBUX or Builders Club. They are sold for $10, $25, $40 and $50 and can be found at various places like Toys R Us, Wal-Mart, Target, Best Buy, GameStop, EB Games, 7-Eleven, etc. Toys я Us cards were released earlier than 7-Eleven cards, at September 26th.