You Don't Smell Right

You can sniff out fellow werecreatures and master impersonators alike. You gain scent as an imprecise sense with a range of 30 feet or extend the range of your scent by 30 feet. When a creature that's transformed into another form or is Impersonating a specific creature passes within range of your scent ability, the GM rolls a secret Perception check for you to realize that the creature is transformed, even if you didn't spend an action to Seek. When you actively Seek a creature within range of your scent, you gain a +2 circumstance bonus to your Perception check to determine if it's disguised.