The Statuette of a Dog, otherwise known as Barbas, will travel into the Hero's knapsack and disappear from the shrine after they speak to Clavicus Vile. He will repeatedly speak and attempt to convince them that battling the Umbra is a bad idea. Barbas will respond accordingly depending on each option taken during the quest. Once it is finished, the statuette will return to its original place on the shrine.
"Hello? Hey! Pay attention! In your pack. The dog. I swear, you heroes aren't particularly quick on the uptake.... Good. Got your attention. I'm Barbas, the Hound of Clavicus Vile. Not that I've always been a hound, or always been called Barbas. I've also been a Redguard. For a while I was a scamp, making deals with Orcs. But, for now, I am His Hound, and I serve the Lord Clavicus. A word of advice here. You've made a bad deal. This Umbra -- bad business. Things always end badly where that one's concerned. Clavicus has always been a little blind to that. And it'll end badly this time, too. So, just leave things be. Walk away. It's your best bet, really."
(After talking with Umbra)
"This is your out, friend. Leave it alone. How about we just march on back to the shrine and tell Clavicus the deal is off? Sure, he'll be a bit put off, but you won't be dead. At least, you probably won't. That's better odds than you're getting here."
(If decided to kill Umbra)
"I'm telling you: don't bring that sword back to Clavicus. It'll ruin him. I'm sure. I mean, not completely: He's still a Daedra Prince and all that. Look, keep the sword if you want. That's your decision. But don't give it back to Clavicus. He doesn't know what's good for him sometimes."
(If decided to leave Umbra)
"Good move, kid. Some things are better left alone. Let's get back to the Shrine. I'll smooth things over with the big guy. I'm sure he'll understand."
(After returning to the Shrine)
"Oh, well. Been good knowing you, kid. Back to being His Hound for me. As for you... good luck, I guess. I've met worse."