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+# What it Does
+This tool replaces a particular kind of node with a rectangular volume of a target node.
+Ie, you click on the ground and a 3x3x3 mound of dirt appears, which can be other dimensions, materials, etc.
+Limited to only placing a maximum of 1024 blocks, but this can be changed.
 
+# How it Works
+The first three inventory slots determine how this tool behaves.
+Slot one, two and three determine X, Y and Z dimensions, respectively.
+Shift + Left click sets which nodes to replace, and Shift + Right click sets which nodes to replace it with. You can select air by clicking anywhere there isn't a block.
+Left-clicking places nodes in the ground, right clicking places nodes on top of the ground.