> For the complete documentation index, see [llms.txt](https://eggverse.gitbook.io/eggt-documents-1/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://eggverse.gitbook.io/eggt-documents-1/about-eggverse/09.-multichain-for-ncr.md). # 09. Multichain for NCR

Figure 11. On EGGVERSE’s own platform, Opensea’s NFTs can be traded without the owner registering the transaction on EGGVERSE

As a new NFT marketplace, the EGGVERSE team recognizes the limiting situation in terms of transaction volume and user acquisition, analyzes the characteristics of the NFT exchange transaction volume distribution in the current NFT market, and considers versatility and scalability as a preliminary development stage of intelligent mainnet analysis technology. developed EGGVERSE technology. The EGGVERSE team developed a smart contract to establish an environment where NFTs traded in EGGVERSE can be automatically listed on Opensea through Opensea API linkage so that EGGVERSE's NFTs can be naturally exposed to Opensea users. In addition, through the linkage between Opensea's NFT API and the EGGVERSE exchange, NFT owners develop a smart contract that allows Opensea's NFTs to be automatically registered in EGGVERSE and traded in EGGVERSE without a separate transaction registration process. increased its scalability by 40% of the market. figure 11 shows that Opensea's NFTs are listed on EGGVERSE based on items such as price, minimum price, price change rate, number of transactions, and base mainnet. Listed NFTs can be traded on their own in EGGVERSE. Above all, EGGVERSE proposes NFT-compatible re-trade technology that allows transactions to be made even in the case of self-issued NFTs issued by EGGVERSE and external NFTs that are not included in the collection NFTs registered in EGGVERSE. Users can trade all the NFTs they own through the proposed NFT-compatible re-trade technology simply by accessing EGGVERSE and connecting web3.0 wallets such as Metamask and Kaikas.

Figure 12. NFTs issued in EGGVERSE can be linked with Opensea, enabling secondary transactions in Opensea

Figure 13. Multichain structure of EGGVERSE

For perfect NFT-compatible re-trade technology support, EGGVERSE plans to develop and support multi-smart contracts (MSC) that can be paid with any cryptocurrency regardless of the type of NFT-based mainnet. As a first-level support for this, the EGGVERSE project will provide a complete blockchain experience by on-chaining all auction and reverse auction data by issuing and trading NFTs through the NFT mainnet that buyers want for all products. Figure 13 is the proposed multi-chain NFT structure and payment structure of EGGVERSE. Multichain support is the first technological step for trading all NFTs on the EGGVERSE exchange platform. Currently, it is possible to trade Ethereum, Polygon, and Klaytn through EGGVERSE, and will continue to expand to Solana, Flow, BSC, EOS, and Wave.

Figure 14. Escrow Smart Contract System of EGGVERSE

The EGGVERSE team recognized that providing safe real transaction services like a centralized platform as a key task in implementing O2O services that deal with real things in the NFT marketplace, and implemented the escrow smart contract. Figure 14 is EGGVERSE's escrow smart contract system. When a seller registers a product, the buyer bids on the product, and the cryptocurrency used in the bidding is transferred to the escrow smart contract as collateral. Buyers can increase the reliability of transactions by sending DMs to sellers. Afterwards, when the auction closes and the successful bid is completed, the seller ships the product to the buyer, and the buyer who receives the delivered product checks the product's condition before proceeding with the purchase confirmation process and the cryptocurrency deposited in the smart contract is sent to the seller. And the NFT is sent to the buyer and the auction is closed. In a word, EGGVERSE is the first in the world to support secure transactions in a trustless manner for real objects. The decentralized NFT metaverse platform of the EGGVERSE project avoids issuing only tokens that are traded or using tokens issued from actual commercial services only as a simple payment method without developing the platform. In fact, unlike other projects that provide unfinished blockchain platform services, EGGVERSE is currently providing the commercialized NFT marketplace services and platforms using multichain technology, partially universal standard and a decentralized system.