Mythic Kil'jaeden would like a word with you. 15% raidwide there would be a huge boon because sometimes things are almost second tight - you are not in the right spot right at that moment - gg go fishing in the nether. I can only imagine how it was initially when orbs were much worse than they are nowadays.
Don't think that could be done without movement boosts.
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I am really happy it's not that, I am quite please it's what we got because it's both damn powerful and unlike a buff - it offers additional incentive for the raid to keep warlock safe/rezzed.