Preheat the oven to 375°F. Lightly grease a loaf pan or line with parchment paper. In a large bowl, combine the ground buffalo, breadcrumbs, onion, eggs, ketchup, hot sauce, garlic, salt, pepper, and half of the blue cheese. Mix gently until combined, being careful not to overwork the meat. Transfer the mixture into the loaf pan and smooth the top. Drizzle additional hot sauce over the top. Bake for 50 to 60 minutes or until the internal temperature reaches 160°F. In the last 10 minutes of baking, sprinkle the remaining blue cheese on top. Let rest for 5 minutes before slicing and serving.