Exclusionary operators don't seem to work in the card database. For Example, e:Alolan returns exclusively cards with Alolan in them. I also can't seem to exclude with the NOT operator, though that may be user error. While not documented and potentially not a feature, I do recall the - or ! working in the past to exclude a value. I may be mixing this up with another site. The two seemingly do nothing.
The intent is to exclude keyword:rule to return Pokemon valid for Gym Leader Challenge.
Furthermore, the help page https://pokemoncard.io/help#card-database mentions format:glc being valid for my goals, but this still returns Pokemon with rule boxes. It is also not present in the built in advanced filter format list. The exclusionary operators not working as expected seemed larger in scope.