Stronghold and Fortress are two types of buildings for the same gameplay. Fortresses grant better rewards.
Alliance Leaders are required to confirm the Fortress/Stronghold they want to attack and select 3 different times for the matchmaking of battle time. The server will then decide the final battle time based on the selections of the Alliances registered to fight for a Fortress/Stronghold.
If it is your first time participating in the battle, you can only register to attack one Fortress or Stronghold
If you have occupied Strongholds/Fortresses in the previous season, you will automatically be registered for the battle of your occupied Strongholds/Fortresses. Besides, you can register for one new Stronghold/Fortress.
You have controlled Fortress No. 5 in the previous attack, so you will automatically be registered for its battle.
You can also select a new Stronghold/Fortress to attack.
The two actions grant different rewards. You may tap Fortress/Stronghold and tap “View” to check the rewards and rules for a better understanding of what you can get.
After the registration ends, the battle time will be shown. When the battle starts, you may rally to attack the Strongholds/Fortresses or attack them alone. Be in control of the Strongholds/Fortresses for more than 30 minutes to occupy them. If no Alliance has managed to occupy it for 2 hours, the Alliance that is in control of the building at the end of the 2 hours will be the occupier.