Mask Layer Style not Found

For whatever reason I cannot seem to locate the mask layer in the ADD LAYER dropdown. I am using Toon Boom Animate Pro 2. The video tutorials seem simple enough but I have no Mask layer.

Screen Shot 2014-05-22 at 10.42.14 PM.png

Drag the Cutter module from the Module-Library into the Network-view.|Toon%20Boom%20Animate%20Pro%203%20User%20Guide|Chapter%2012%3A%20Character%20Building|Rigging|_____8

Thanks nolanscott! Is there a way to mask multiple layers with the same mask shape?
In the Network View, I try to connect additional objects to the cutter module but it just replaces the node instead of adding a new one.

Or to put it another way: Can you mask grouped layers?

Never mind! I figured it out. Thanks again!