NFTs Composition Rules

Because any high-level NFT must be obtained through synthesis, synthesis is important, please understand the rules of synthesis carefully.
Users have the opportunity to use two NFTs of the same level to synthesize an NFT of a higher level. For example, two NFTs of level N can synthesize an NFT of level S. 
There are two points to note here: 
1. Requires 500 SNT to synthesize and cannot proceed without it.
2. Even if you destroy 500 SNT for synthesis, the success rate of synthesis is 50%. The synthesis may succeed or fail. If it fails, you will lose the 2 NFTs used for synthesis, and they will be destroyed, so before synthesis, please Think carefully, don't blindly synthesize.
S+S = SS  demo