Legionslayer I

Easy to cheese/farm this while on the Val'sharah quest To Old Friends

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• Just ask a friend to make a timerunner alt to create a raid group with you or log a second acc yourself
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• Spam your action button macro on mobs u tag until u get achie/click ExtraActionButton1
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• GG
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Difference between "Empowered Enemies" and normal enemies is empowered ones having these 4 different debuffs. You can identify them by small visuals they have or from debuffs tab in their name plates;

Imperious: Exact same yellow-red icon on their head. Check icon by clicking wowhead link of Imperious.
Beacon of Chaos: Mobs with Beacon of Chaos has a green shard top of their head.
Fel Raiser & Engorged: I saw them together on same mob and mob had 2 orb spinning around it, one is yellow other is red.

You need to kill these to get the achi.

Fun fact -- when using Felspike (Twisted Crusade / Fel path) as the killing blow it will NOT count towards any Legionslayer achievement.