I like it - sounds like it could give a Warhammer 1e feel in some ways. Would definitely be good for a game of more "survival horror" feel.
Need to add a Rat Catcher background for full Warhammer 1e effect though.
Found in the backstreets, alleys, basements and sewers of many a village, town and city ratcatchers make a living by disposing of the vermin that infest the dark corners of civilisation. Their unsanitary job often makes others feel uncomfortable, nonetheless ratcatchers often hear and see things others miss as they spend long hours in dark, confined spaces studying the habits of rats and other vermin, often gaining an uncanny understanding of their prey in a lonely, dirty job that helps keep the plague away.
Skill Proficiencies: Perception, Animal Handling
Tool Proficiencies: Thieves tools (Traps), Poisoners Kit, Flute (Wind instruments)
Equipment: A set of common clothes including a long leather coat and rain hat, rat traps & cages, sling* with 50 ammo, a silvered club, a skinning knife, a belt pouch containing 5 gp and a tiny vicious dog.
Feature: Tiny vicious dog: You are accompanied by a tiny stray dog that you found in the streets and trained to help you in the ratcatching trade. The tiny dog has advantage on Perception checks that rely on hearing or smell, and will growl viciously at anything it notices. The tiny dog never goes more than 30 feet from you unless you use a bonus action to order it to dash out to bite a target or to hunt through cramped conditions (60 ft range), after a succesful bite the dog will immediate pull back towards you. (Spd 30, HP 1d4 AC 13, +5 to hit, reach 5’, Damage 1d4)
Feature: Sewer Explorer
While navigating the less frequented back alleys, basements and sewers of an urban setting you can move quickly through confined and difficult terrain without being slowed down, you can’t become lost except by magical means and your dog will alert you to danger even when you are engaged in another activity while traveling (such as foraging, navigating, or tracking
While tracking vermin you can learn their exact number, their sizes, and how long ago they passed through the area.
Custom Sling: You gain advantage when using your sling against Small and Tiny beasts.