Im not an expert at jass or anything, but is there a command that i can use to allow a units attack range to increase/decrease. i know WEU can do it, but i dont like 3rd party editors.
There's no trigger action to do this.
In WEU it's done with a range upgrade with almost infinite levels, and another negative upgrade that will reduce the range again if needed.
I guess that's the only possibility to pull it off.