Masks

What are they?

Masks are (arguably) as useful as patterns, but you'll probably use them much less. They define which blocks in a region will be affected when you perform an operation.

The most common use of this in WorldEdit is in the //replace command. For example, in the command //replace stone 50%diamond_ore,50%emerald_ore, the mask is stone, which means that only stone will be replaced by the pattern.

Getting a mask is pretty similar to getting a pattern; they can be created using an itemtype or string, but can generally be less complex due to their nature.

For more information on masks, and how they work, check out the WorldEdit mask docs.