I searched up common slugs and found it referred to as a Leopard Slug, though I see now Wikipedia says Tiger Slug is another common name for it. Is Tiger Slug a more common term here?
I also see that my one is only a baby, with adults 10cm-20cm long! Leo is probably about 7cm except when stretched out. I'll have to keep him well fed and see how big he gets!
Yeah I've always known them as tiger slugs. Yes they get pretty big, and dark. He will probably enjoy it if you feed him some kind of wet catfood, they also drink water.