Orcus

Orcus is the demon god of undeath and necromancy. He is wholly evil and enjoys torturing and corrupting mortal souls. Orcus' presence in the adventures of Vox Machina is very significant as one of his artifacts, the Horn of Orcus, is obtained by the mad beholder K'Varn, who is the primary antagonist to Vox Machina in for the first several episodes.