Peritas The Greyhound
If you know anything about Alexander the Great then you know that he was an amazing conquerer. The legend is that he had his beloved dog Peritas. Peritas was a gift from a Greek King so you know he was of huge value to Alexander. The legend continued when it was said that Peritas once took down a lion and an elephant.
Not only was he Alexanders companion in battle but also in life. After the passing of his precious dog, Alexander named a city (that was said to be somewhere in India) after him.