Synthesis is an exciting feature that allows players to upgrade different items within the game including Runes, into more potent assets, such as a higher level Rune. However, this process isn't guaranteed to be successful every time, and involves the use of $ES as a fee for each attempt.
Despite this potential for failure, each unsuccessful synthesis attempt increases the chance of success for the next try. Additionally, the amount of material required for synthesis increases with each failure, making the process a balance of risk and reward.
Each type of synthesis has its own specifics regarding the number of materials needed, the amount of $ES to be spent, the success rate based on the number of previous unsuccessful attempts, and the potential rewards to be earned.
Please refer to the graphic below for a detailed overview of the specifics for each type of synthesis.