Lurchers are the ultimate in poachers dogs. They were the common man's way to own a greyhound without contravening the law of the land that said only nobles could own them. That was punishable with death BTW.
The lurcher is a cross animal which means it is likely to be healthier and longer lived than a pure bred. A typical life expectancy is 14-16 years and 20 years plus is not uncommon. Why is this important? Well you train a dog to help in a hunt you want to have as long as possible use of that trained skill don't you?
Lurchers are fast, good for the kill, they have good instincts (mostly) good for the killl, they were traditionally bred for intelligence as poachers would leave them with a down command when the game keeper turned up. The dog would stay in the undergrowth for hours out of sight and on its own before the poacher came back for it. They often have a hardy coat (rough coated or partly rough coated are best, think the shaggy dog look such as the lighthouse keeper's dog in Fraggle Rock) this is good for undergrowth and weather whereas a greyhound would rip its skin.
AS far as what the lurcher could get, well lets just say rabbits are an obvious one. Another animal a lurcher can get is deer. Don't ask me how I know, ok a relative had a lurcher in a well known southern national park with very medieval laws. It used to barrel into deer and knock em over. A second dog was usually close enough to make the kill. That is why you should have two dogs and why you should never own a lurcher with very strong chase instincts in the New Forest as it can not always be trained out of it.