Terraria Editor
"If you didn't mine it, you didn't earn it. The struggle of grinding for the Rod of Discord is what makes the game rewarding."
Navigate to the "Liquids" tab. Select "Water" and dump a massive bucket into your new arena. terraria editor
Use the zoom tool to find the corruption chasm. Select the "Paint" tool and change the brush size to 10. In the block palette, select "Dirt" or "Stone." Now, click and drag over the chasm. Poof. It is filled. "If you didn't mine it, you didn't earn it