First fucking terrier I've pwnt. There is a sheer, bloody determination there that was missing from the more instruction friendly Shepherds and Labs I've had before. This little bastard will give you 110% attention up until such a time as a rabbit or squirrel crosses his nose. He chases deer. Never catches them. It's good exercise for him. I'll sic him on them. "Rabbits!" I never bothered breaking it down - "food smelling animal to chase - go!" "Rabbits!" one size fits all.
From that moment on, until he finds himself alone in the woods, quarry gone, and none too sure where I am. Then he'd take a recall command but he doesn't get one. I've hidden behind a big fat old scots pine. If a dog is in the habit of fucking off on its own and refusing to come back, one logical human reaction is to chase after it. Dogs love this. And will run away for hours. I've seen them playing this game down the park with owners who are fucking clueless to what's going on. He gets cocky in the woods - "I can always find them they shout and yell. No worries. I'm off in here."
However, I take him up the woods and off he goes and I shout once and then hide. Every time he disappears - duck down in a ditch or something. Pretty soon he gets the message I want him to get - "I have to keep an eye on this bastard."