I used to have a Rotti, he was a gentle giant in all possible meanings. Maybe he pulled me off my feet once or twice when I would play tug of war with him as a kid, but he never ever gave any of us sustainable injuries. Best dog we ever had.

Now, my Shih Tzu can be a little wildfire. She growls if she's relaxing and you sit too close. She barks if the couch is full and she can't find room to sit that isn't touching someone else. And her jaws are made of steel, I'm still healing from a nip I got from her last week while playing tug with her favorite toy. She broke the skin just a bit, and the bruising was much more than you'd expect from a 35 pound dog.