Negative numbers

I was wondering, how do you make spells having negative numbers without triggers or the JASS things. is it even possible?
Example: Devotion aura which works on enemies and takes off armor instead of adding.

Hold down shift and double click on the field, it allows you to enter negative values. This question is being asked a lot lately, and is, I believe, also answered in a stickied thread "handy WE tips". Search a little before you ask next time.

Hooray someone said shift-clicking first! :D

You can also go to preferences and set the editor to accept negative values, but shift-clicking is more useful. You dont need to set it to accept negative values if you shift-click either. Try shift-clicking with other fields in the editor and see what else its useful for.

Well, I was going to say the other possibility first, but then I couldn't exactly remember in what menu it was, so then, with heavy heart, I suggested shift-double-clicking. ;) I otherwise don't use shift-clicking, I just set it once under the preferences and now I can fill in anything I want everytime.