Death-worshippers are followers of the teachings of Shintal. They may bear the mark of their god;

A surprising number of them have the same tattoo, a skull with the number “3” inscribed over its forehead.
…
“That’s the symbol for Shintal, the three-headed Goblin god of death.“ - Pulgor - Festival of Heroes (GS-ADV1)

A surprising number of the patients have the same tattoo on their left shoulder: a skull with the numeral “3” written on it. - Festival of Heroes (GS-ADV1)

At the time of Queen Gimnax's rule, cult worship of Shintal was forbidden;

You interview a few of the death-worshippers, but they’re understandably tight-lipped when it comes to discussing the cult. Queen Gimnax recently outlawed the worship of Shintal. - Festival of Heroes (GS-ADV1)

• Azema
• Lady Bork Ungerton

When playing with the Lead Medallion in the Ossuary of the Old Order, you stumble upon one founder of Ulos;

A small plaque near these bones names them as Lady Bork Ungerton, member of the Council of Founders. - Outbreak in Undercity (RPA-ADV3)