Mechanics make a raid challenging though, and spire of stars proved that. The extreme intensity of the adds and the heavy mechanics make it the hardest raid in D2, it's also why I love the raid. D1 lacked heavy mechanics in most of the raids, which is what made them much easier than D2 raids (with the exception of king's fall, the only raid to feature intense mechanics that required almost flawless execution) I personally enjoy the heavy mechanics in D2 raids. Sure wrath of the machine and vault of glass are enjoyable, I feel they're just to simplistic. Crota doesn't count as a raid.