Challenges consist of achievements and repeat missions.

1. Achievement
- Complete objectives to earn rewards. 
- Achievements can only be completed once.
- For step-related achievements, the progress will accumulate in the next step even when the step reward has not been claimed. All rewards can be claimed at once whenever you want.
E.g., After completing the [Normal Scout] Attempt 10 times achievement, you can proceed to the next step of [Normal Scout] Attempt 30 times without collecting the reward for the completed step.

2. Repeat Mission
- These are missions that can be completed repeatedly. 
- Rewards are granted based on the records achieved in a game. Playing manually will earn you more rewards.
- Complete a mission step to earn a step reward.

① Check the list of achievements and their rewards.
② Check the list of repeat missions and their rewards.
③ Manual play will earn you a bonus reward.
④ Completing each step will additionally earn you a step reward.