http://www.wowwiki.com/Mechanicals на вики сложно было заглянуть?
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Not having blood as such, most mechanicals are immune to bleed type melee attacks: Rend, Garrote, etc. They are also immune to draining abilities, such as a warlock's Drain Life spell. They are also immune to the fear spell. Not counting un-categorized mobs, they are the only monster "family" that cannot be tracked by a hunter.
сами переведете? автор, вы не правы