Snoopy?
Killer chihuahua? 8>)

I have a fifteen-pound Havanese, a great watch dog, and very protective. I think she would do it.
We have a 14 lb Chihuahua that will eat your shorts. The UPS guy will not come on the porch. LOL!
Small dogs are highly underrated. I underrated them.
I was on a walk a few years ago when a small brown dog about 10 pounds, charged me. I was able to holler at it and make it back off. I continued my walk and the same thing happened on my return. In neither case had I provoked it by any normal standards.
Because of the numbers of kids in the area playing in the street, and observing similar behavior toward others on the part of the dog, I made a police report. The officer took it down and I could see it was not taken as a big deal.
After several hours, we had a knock on the door. The police officer who had checked out my report was himself attacked and only his thick boots protected him from injury. The dog was a menace and was eventually euthanized.
It made me sad, but this dog was going to injure someone seriously. There are a bunch of important arteries in the ankles and legs.
That crook was wise to get out of the house! In this case the small dog ferocity was appropriately placed! Thank God for our small protective friends.
If you think Americans don’t treat dogs well, take a trip to Europe. There, dying dogs wander the streets and empty lots, missing legs, with terrible wounds, afraid of people. It would make you cry. Here at home my sister-in-law and I saw a dog chained to a stake in a front yard, actually covered in ice, shivering. She stole it and it was the most loving, thankful doggie until it died a ripe old age. If you want a dog or cat, please adopt one from a shelter.

I have a chihuahua and a Shih tzu.
I dare anyone to come into this house unannounced.
My three raccoons will attack any intruder near the porch and begin to eat him for lunch. They are very territorial. My sister also had a raccoon that guarded her van.