Plugin VoidGenerator
Very basic world generator. All it makes is void; except one block (which, by default, you will spawn on) of bedrock, that you can use as a base to build, as you need a block to place another block. It's useful if you want to keep users enclosed in an area, as even if users escape from whatever you build on the map, they don't have any other place to go.
Official URL : http://dev.bukkit.org/server-mods/voidgenerator/
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