GAME SYSTEM This entry is to allow for discussion/rating of the game system as a whole. It is not for a specific product or release. Versions will appear on the individual item pages. ChaOS (character operating system) is a trading card game published by bushiroad. Like weiss schwarz, you can use characters in popular animes or galgames.Your Main Deck is built from 50 cards, including characters, events, set cards, and the like. You may have up to 4 copies of cards with the same name. Extra cards can't go in your Main Deck; you may have an Extra Deck with up to 10 cards. If your Extra Deck has under 10 cards (for instance, 0) you can still play the game. In Chaos TCG, your Main Deck is your Life. Each player's goal is to reduce their opponent's Main Deck to 0 through attacks and card effects.