"The perfect pet at the perfect price -- guaranteed." Creature Dex at the bottom of the sub, if you want to include "relatively harmless" alien critters in your campaign.
The city was cursed many years ago. Since then it has not stopped raining. The gutters are inhabited by eels and the doors are on the first floor, coated with pitch. On a bad day, you can see the water level rise above the ground floor windows. Carts have both wheels and bladders filled with air to keep them afloat. And yet everyone is surprisingly dry.