[Aaron]

Don't sweat it, everyone has to start somewhere, and you're starting about where I did.

Almost everything in the editor has a "General Information" section at the bottom. One of the buttons there is "User Tags", click on that and the first option is "New tag". Check that and click "OK". It'll pop up a new window where you can choose the Tag Unique ID (which has to be 10 characters or less), the Tag name (which is what is fetched when tagnames is called for the tag) and the Tag abbreviation (similarly, called by tagabbrevs). All tags created here have the Custom tag group.

So if you're going to go with Custom.wFeran for your tag, make sure you define it on one thing, then bootstrap the weapons with the tag, then alter the script you posted above to look like this:

~change the size of our natural weapons
      var searchexpr as string
      searchexpr = "Custom.wFeran"      
    
      foreach pick in hero from BaseNatWep where searchexpr
        perform eachpick.assign[Helper.DamageUp]
        nexteach