Prince of Persia: Warrior Within
The Prince has been chased by the Dahaka for sleepless nights. He and his army set sail for the Island of Time. If the Prince doesn't get all nine health upgrades and the Water Sword, he has Kaileena as the final boss. He kills her and the Dahaka takes the Amulet of Time from him. If the Prince gets all nine health upgrades and the Water Sword, he has the Dahaka as the final boss. The Prince learns that the Water Sword is effective towards the Dahaka.