Denath appears in the Demon Slayer and Shadow of the Storm quests, where he is trying to raise the demon Agrith-Naar. In fact, it is revealed he is Agrith-Naar and was trying to banish himself back. The player must kill him by raising him again.
Shadow of the Storm
During Shadow of the Storm, it is revealed he has fled to the ruins of Uzer, where he has been building up a following of supposedly evil, but actually quite friendly, people. They aid him in the summoning of the weather demon Agrith-Naar, but during the ritual, he steps in the middle and is transported to the Infernal Dimensions, meaning that he is Agrith-Naar himself. This also explains his relation to Delrith and the similar marks on his chest. After most of the members of his group get killed either by monsters or the sandstorms he caused, the same adventurer who killed Delrith summons him with a new group of people and defeats him. At the summoning, however, Agrith-Naar kills Matthew, a former member of the group who had aided the player during the quest, after already having killed Josef in between the events of quests. As Agrith-Naar dies, he and thus Denath are gone for good.
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