Smoke bombs and flares won't kill em at all, it just inconviniences them for a bit. The only way to get em is traps, and I vastly prefer the gut hook style..
Like oldman said, get under the mound and you'll find two tunnels, going off in diff directions. It'll take a little pokin around but widen them both out enough to get a trap in each one. Set it a little ways back in the tunnel and put somethin over the hole to keep the light out. You get some dumb ones that stumble right on into their funeral, but you also get some smart bastards. Those are the ones.....
Those are the ones that turn it into a sport. They test you. They outsmart you, again and again, till you've turned your backyard into a lunar landscape tunneling further and further to get that perfect trap set...
And when you get that big elusive bastard...whose taken down 3 of your prime tomatoe plants, and countless other lesser vegetables....that's your time.. Celebrate your victory..
I usually throw em in the roof and let the owls get em.
