So it's possible to actually kill the zombie dogs?

[Sequiro]

Forgive me but in spooky games like this I like to hold no punches so I spiked the difficulty all the way up to hard mode.

I have as yet been able to kill a dog. I've thrown a rock at it and it just gets up and kills me in two bites

I threw 2 sticks of dynamite at one and it just seemed to piss it off. The few times I've charged it with my hammer or ice pick I've never even got a hit off on it before it slaughters me.

They seem invincible at least on hard mode. So I've been just running from them and hiding in the shadows.

[Penumbra]

Nope, you can kill them. I just crouch down and hold my hammer back and wait for it to charge. When it does charge, its all about timing. Once you knock it down the 1st time, you can easily kill it.

[djc23]

You can also hop up onto a crate, sometimes you might need to bring something to step up on, and whack safetly as it jumps at you.