There are total of 255 levels, and all trainers start at level one upon minting (recruit). After each victory battle, a trainer will gain some experience to level up. To level up to certain checkpoints, a trainer also needs to do a fusion apart from gaining enough EXP.
Higher level will have higher power and higher payout reward in every battle.
Every ten levels is a milestone: 11, 21, 31... where a trainer receives a huge boost in power and reward payout.
Fusion is a process of merging 2 trainers together to reach certain levels. One of them will be burnt. Fusion is a mechanism to reduce the amount of available trainers in the game. It helps to mitigate the inflation rate and make the remaining trainers more valuable.
Level 11, 21, 31, 41, 51, 101, 151, 201 are currently fusion checkpoints. To pass these levels, you will need to make a fusion apart from having enough experience.
Please refer to the Fusion page to learn more about it.
Please refer to the table below to see how much EXP needed to reach the next level or milestones and the corresponding power in each level. As you can see in the table, after each Fusion checkpoint, the power will increase dramatically, giving out more rewards as a result.
Experience Table - July 24rd, 2021
More information on how trainer power is used to determine battle calculations and payouts can be found here:
The accumulated experience of all trainers through battles are displayed in the Rewards bar in Trainers tab. You can click to it to claim them all at once.
For those who reached the fusion checkpoint, you need to make a fusion to be able to claim more experience for that trainer.
Because claiming experience is actually a blockchain transaction, it will cost gas fee. Thus, if your trainer level is low, it's recommended to wait until they gained enough experience to reach the next milestone before claiming it.