Two empires clash for control of the Imperial City in this four-stage event:
- Matchmaking (24h): View rules, empire details, and partial rewards.
- Preparation: Complete tasks to earn points. The empire with the highest total becomes the invader.
- War: Governors relocate near the invasion camp to battle. If invaders win, their king rules both empires; if defenders win, their king retains power while the invaders’ city remains leaderless.
- Recovery: Lost units can be restored, final scores are tallied, and rewards are sent via mail.