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The campaign modifiers window is available in the upper-right set of campaign tool buttonsTool buttons near the top of the Sidebar. The GM can build a number of modifiers that can be applied quickly to dice rolls.
To create a Custom modifier, click the green 
button at the bottom of the window. Fill in the description for the modifier entry and the number you wish to modify rolls by. Make sure to denote whether they are positive ( + ) or negative ( - ).
To apply a modifier from the Custom list, click the plus+/minus - button next to of the modifier name and the numerical modifier will be added to the Modifier Stack. To hide/show a modifier in the player modifiers list, click the eye icon on the right side of the modifier entry.
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