What kind of mix is this?

[Emma & Poppy]

Looks like a Dane MIX / Border Collie

I agree there, I was going to post that exact mix!

[ontariogreys]

He is a mulitple mix, I know there are a few borzoi's around but not enough that I would pick saluki or borzoi,and an actual wolfhound is even rarer, as the sighthound possible mix I would say greyhound some breeders will adopt them out privately without having them fixed first so that may be where the arched back comes from. I do believe he has some border collie and without knowing the height or weight and no reference in the picture , it is hard to say what else he may be mix with though Dane is a good possibility or some hound mix

[Giselle]

I agree with OntarioGreys. There are very very few intact Borzois and Salukis running around the United States, so I highly doubt the dog is a Zoi/Saluki mix. Plus, nearly all sighthounds possess that "arched" back, including Iggies and Whippies ;] The dog is most definitely part sighthound, but I would not say Zoi or Saluki. On the contrary, there are literally hundreds of thousands of Greyhounds, many of which come from racetracks, and, from time to time, an intact ex-racer does make it out. We're trying to prevent that more and more, but the inevitable does happen. Grey/BC mixes are also quite prevalent down in my area, so I can definitely see both breeds in King.
For those reasons, I'd say this dog is a Greyhound/Border Collie/Dane mix.