Overzealous

Every now and again, you think Blizzard named an achievement after you - but then you realise they didn't.

Damn you, Blizzard.

Very easy to solo now if you have a decent item level, at least as ranged. Just did it today as a 704 hunter.

I've seen some comments stating that the bugs spawn in the last phase, but I can confirm this is incorrect. The bugs needed for the debuff actually spawn as soon as you start the encounter - just look at the base of the pillars for tiny glowing insects. They are lootable.

After picking one up and gaining the debuff, pop everything, get him down quickly and you'll get the achieve. Unlike some of the other achieves this does not require a certain number of players.

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• The debuff is a 30% movement reduction and remains for the entire fight, even if you are dead.
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• There are 8 bugs at a time in 10 player mode, 2 near each pillar.
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• The bugs respawn (after what seemed like a minute, need clarification about how long).
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• It is still very easy to avoid attenuation by strafing back and forth between the orbs.
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Because there are only 8 bugs on 10 player, you must have 2 players pick up bugs early and wait for respawns. Assign the 8 other people to pillars so they aren't wasting time running all about the room.
The trick to this achievement is to have your first two players grab bugs on the way to the 3rd platform. That will let the bugs respawn earlier. On our successful attempt, they either respawned while we were still on the 3rd platform or shortly after the transition to the last phase (didn't pay close enough attention).

We tried getting our first two bugs at the beginning of the last phase, but they didn't respawn quickly enough. We had to stop and wait excessively for respawns, at which every time someone would happen to die without the debuff. I don't recommend trying it this way if your group has to stop dps - it only makes the fight take longer and gives more room for error.