Call of Duty: Black Ops 3 Zombies (DLC #4 Salvation) - Controlled Chaos - In Revelations, override all of the Corruption Engines before round 6. [Bronze / 15G]

For this trophy / achievement you must have activated all 4 Corruption Engines by the time round 6 ends. This isn't all too difficult. Use your knife and pistol in early rounds to get lots of points. Activate the engines as you come across them and open all doors. Don't waste your points on perks. A shotgun is all you need.
After activating an engine you must stay alive for a few seconds. Lots of enemies will spawn. You can either run in circles and avoid them, or use the shotgun to one-hit kill them (this is safer). Each engine costs 500 points to be activated. It's far easier with multiple players because everyone starts out with 500 points, allowing you to open more doors right away.

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