Black Magic

You have to love the material cost. 666.

The new Black Magic:

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• +250 Haste rating
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• 10 second duration
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• 35 second Internal cooldown
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• 35% proc
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• proc is roughly equivalent to 67-68 haste rating all the time
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• cannot be dispelled
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Analysis

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• excellent enchant for casters that value haste > or = spellpower
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• Better than 63 spellpower, but not 81 spellpower for many casters
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• good enchant for offhand for rogues (poisons) and ench shaman
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• shared cooldown and does not stack* with itself (therefore do not apply to both weapons)
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• high % chance to proc so count on it happening within 2 seconds of the internal cooldown
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• berserking is still slightly better for offhand for rogues according to current simcraft.
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* Haste procs from different sources now stack, but not the same source. Note that you can never have multiple haste procs up regardless of the source. They ALL share a cooldown. So Black Magic will not work with Hyperspeed accelerators or that haste trinket you just activated. It will work with Heroism since that's not a haste proc and uses different mechanics.
thanks to JV3r8.

The "glow" effect is the same as on Unholy Weapon, i.e. small green skulls flying around the weapon.