Not endless battle between good and evil ... Sentinel vs Scourge.
Want to make slave scourge of the whole world. But let this enforcement accomplishments, the Sentinel?
Of course not! They will do everything to protect bringing life into the world, the World Tree. They prevent the conception of the Scourge to World domination by breaking the Frozen Throne, the seat of the head of the Lich King Scourge was to completely abandon the world of evil.
Who will succeed, the Sentinel or the Scourge?