To kill Vivec, a god who has an entire metropolis dedicated to him, its actually rather easy. First, you'll need to be abel to pick a 100% Locked door, then you'll confront the deity himself. Don't attack him with a sword, simply shoot something at him. He'll attack you with magic. If you're hit, you're dead, simple as that. Once he's missed twice, he's defenseless and using hand to hand combat. He has a LOT of health, so be prepared.

Loot hios corpse to find a useless dwemer atifact that just may be not as useless as you think...