"His shotgun set aside, Tory knelt down, intent on sniffing the blood he had found. Age, foreign substances, and other olfactory signals would be among the droplets, all important in their own ways."

As in Werewolf Tale, within the TTRPG, a Werewolf's nose is second to none, if not the best tool they have. In-game, to identify a scent as well as its source, players roll their Intelligence (INT) + Spot Hidden totals, and compare the results to a threshold from 3 to 6, potentially higher when strange, or many, scents are in play. Numbers higher than 6 can be reached with the Exploding Dice rule, I.E. the if-you-roll-a-6-then-roll-again rule.

When playing as a Werewolf however, extra dice are added regardless of form; an extra 2 dice when in human form and an extra 5 when shifted, and the mechanics of the roll change as well. Should a Werewolf player have twice or more dice than is needed to succeed, regardless of the threshold needed to be met, they automatically succeed and can identify or follow a scent until such a time when this no longer holds true and they fail a roll.

Artist -  DeadDragonP (Check his gallery for the NSFW version of this image: https://www.furaffinity.net/view/37796159/)

(If anyone is curious about the shotgun model, it's based on the Mossberg Maverick. Pistol grip/no stock.)