Your overall number of attacks are displayed on the counter which appears once you enter the Islands area. Each time you try to conquer an island, a single attack will be added to your counter. Once your counter reaches the maximum number of attacks, you will no longer be able to take any action within the Ninja event.
Your maximum number of attacks can be increased by conquering certain islands. Those islands have a special notifier which states "+X attacks".
Your attack counter will increase if you take any of the following actions:
- Attack an island (regardless whether you win or not)
- Attack an already conquered island
If you want to complete all missions within the Ninja Event, you must conquer every island on your first attempt without attacking any island more than once.
Please note that you can already advance to the next island once you have destroyed the portal of the previous island, regardless of how many crowns you achieve.