> For the complete documentation index, see [llms.txt](https://whitepaper.cryptoknights.games/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://whitepaper.cryptoknights.games/technical/bridge.md).

# Bridge

### Multichain

CryptoKnights is a multichain game, meaning that the in-game assets can be **imported from and withdrawn to multiple blockchains**.

### RUBY as a Cross-Chain Token

For our RUBY token to exist on multiple chains, we incorporated a **special type of ERC20 contract that can be aware of its balance on other chains**, so that the total amount of RUBY on all chains it has been deployed on remains constant.

### NFT Bridging

The NFTs in CryptoKnights will first be auctioned on a single blockchain, then can be imported into the game and withdrawn onto other chains.

### The Game is a Bridge

Therefore the game serves as a bridge for all those tokens.