If the old raids were to come back (which they should), then they should be made to reflect story progression, and must be done in order to unlock the other raids. - VoG comes first. Prerequisites are to complete the original story line and have a minimum light level of 230. Recommended light level is 250-270 normal, 280 hard mode. Gear drops up to 270 on normal and 280 on hard. - To unlock Crota's End, you must complete VoG on hard and also complete the Dark Below story line, and has a minimum light level of 260. Recommended light level is 270-290 on normal, and 300 on hard. Gear drops up to 290 on normal and 300 on hard. - To unlock King's Fall, you must complete Crota's End on hard and also complete the Taken King story line. Rest is the same as it is now. PoE could also come back, but it would be separate from the raids. Only prerequisite is to complete the House of Wolves story line. Only mode available is hard mode (a.k.a, skolas), and has a recommended light level of 300.