You can upgrade rarity of your NFTs here! If you want to try to upgrade your NFT, you need to choose NFTs to use them for the upgrade More NTFs = higher chances to upgrade.
Be aware - if you fail your upgrade attempt, you will lose half of used NFTs. If your attempt is succeeded, then you will get NFT with better rarity, all used NFTs will be destroyed.
Upgrading system will open in:
If it fails, 50% of the cards will break