Sometimes, tortoiseshell cats might have tabby patterns in one or the two colors. A gray tortoiseshell cat or even a tortoiseshell tabby cat, known as a torbie, can sometimes have a novel color pattern identified as mackerel. I love tortoiseshell cats. My fav is actually a Russian blue tortoise name https://tortoise-eyewear80123.shotblogs.com/tortoise-orm-fundamentals-explained-47846743