I must concur with this... I have also run instances with feral+4xshamans and i must admit that with 4x ele shamans you will storm through EASY instances, but with harder heroic instances you will NEED to have resto/holy healer in your group.
You don't need a healer, 4 elemental shaman is fine for all five man instances. Ive done Heroic HoR the 3rd day it came out with 4 ele, 1 paladin. As well as all the other instances, it might be useful, but not required in the least.
Orbzz, Orbzm, Orbzem,Iceorbs SHM - Lvl 80 Hyjal PvE
Örbz, Örbs, Õrbz & Õrbs 80 Ret Paladin Team Hyjal
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