What is Assets?
As it's written at the-crypto-world, heroes and items belongs to you in My Crypto Heroes. You can freely trade those items outside of the game and even make use of them in other games
In My Crypto Heroes, ownership of digital assets are secured by Ethereum as ERC 721 specification. Those digital assets (ERC-721) has unique number therefore all of them are not fungible. So it's called Nonfungible token (NFT).
There are 3 types of NFT in MCH, Heroes, Extentions(item) and Land.