How do you spawn an Eater of Worlds in an Artificial Environment?

Question

I'd like to build an Eater of Worlds arena but I'm confused regarding what his summon requirements are.

I see some arenas built entirely of wood. The wiki vaguely references corrupted dirt (how much?) and ebonstone (200+).

Answer

The Eater of Worlds must be spawned in a Corrupted environment. There are certain requirements of a number of Ebonstone blocks for an area to be considered Corrupted. I'm attempting to find the exact numbers, but I believe the 200+ is correct. When you're in a Corrupted environment, the music and background will change. By watching/listening for that, you can know whether you can spawn the Eater of Worlds.

Edit: Alright, looks like 200+ is correct.

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