Kickin' With the Wick

The Hallow’s End event has had his dungeon encounter updated. You can now increase the difficulty of the encounter by speaking to the Wicker men at the dungeon’s entrance to enable extra mechanics. These curses are not party wide and afflict only those who enable them. Simply speak to all 4 Wicker Men (to enable new event dungeon hard-mode) defeat the boss and get your achievement. Good Luck everyone...

I clicked the larger central ominous wickerman to accept all curses (rather than each individual wickerman). During the encounter, I dodged the purple swirlies, purple circles, fire breath, and fire pools, killed/CCed my add, and ran to the highlighted orb. I got a stack or two of the wicker man's shadow debuff that lowers health by 10% when I failed a mechanic. After completing the encounter, I earned the achievement.

It is easier on a mobile class like a hunter because you will constantly be running to dodge mechanics. I could tell the mechanics were not affecting or visible to anyone else since they were mostly standing still. Avoid standing near all the environmental objects that make it difficult to move freely in all directions.

More info on each curse. You'll be dodging these on top of the regular mechanics:

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• Wicker Man's Shadow - failing to dodge the curses reduces maximum health by 10% each stack
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• Wicker Man of Embers - Dodge purple swirlies - Cursed pumpkin breath - cursed targets emit shadowflame blasts around their location and inflict a stack of Wicker Man's Shadow
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• Wicked Man of Thorns - Move out of purple circle - Cursed vine march - piercing thorns erupt under cursed enemies periodically and inflict a stack of Wicker Man's Shadow
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• Wicker Man of Delusions - Run to orb with arrow - Cursed hot head - cursed enemies suffer from hallucinations, moving to them dispels them, ignoring them inflicts two stacks of Wicker Man's Shadow
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• Wicker man of Shadows - CC/Kill add - Cursed insidious cackle - cursed targets shed part of their soul, which is shackled and moves slowly towards shadowy flames. Attack and CC the soul to free it before it reaches the flames to avoid two stacks of Wicker Man's Shadow
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*Editing to add: if you don't get the achievement, it's possible you were hit by too many mechanics and lost the curse debuffs when you cheated death via Wicker Man's Protection. If you have raid-style party frames active, you can see the curse debuff and stacks of shadow on each player more easily. It is much easier to fail as a healer/melee class or if more people in the party are affected by the curses.

Seems bugged. I talked to the four wickermen, got the 4 debuffs, we killed the boss, but no achievement.

Edit: did it on three chars, ALSO made sure that in one run EVERYONE had the 4 debuffs. Still no achievement.

Blizz, where is your QA? Stop releasing features that are broken.

PS: thanks Blizz for giving my warlock a soul bound epic plate helmet with a cool function that I cannot use because it's not account bound.

Edit 2: Found a solution for the achievement.

1. Click on the big guy in the middle and then activate all curses via his dialogue options.
2. DO NOT talk to any of the smaller wickers
3. make sure to NOT get hit by his abilities
4. make sure to kill your ghost copy when it spawns, before reaching him
5. When you are linked to a circle on the ground, run there before it explodes
6. kill the adds (we're not sure if this is necessary, but to be sure just cleave them)

Those things can - for some reason - bug the achievement (at least that's the way we could get the achievement to work). In that run that worked we had three people with the debuffs, two people without the debuffs.