The Brand of Samael is a mark identifying those individuals who serve the will of an otherworldly entity of considerable power known as Samael which it was named after, and it is featured in the Silent Hill comic book series. It first appeared in Hunger and reappeared in Sinner's Reward. This sign resembles the iconic symbol of The Order, a local religious cult based in the infamous ghost town of Silent Hill which is warped and haunted by both the Fog World and the Otherworld.
HungerThe brand first appears in a flashback of Whately's, as he relays the death of Officer Eddie Swaggart to sheriff Bryce Canavan. Swaggart had caught a 911 call of a woman claiming she was trapped in an abandoned house, and several, strange and monstrous things were trying to kill her. When Swaggart arrives, he finds Douglas Brenneman's fiancee Rosy bound in a corner, near a wall bearing the Brand of Samael, and the phrase Comes now, the Venom of God. In its next appearance, Douglas, having followed his fiancee, Rosy, into Silent Hill's public library, is attacked by a demonic version of her and is thrown off of a second-story ledge. Falling on a stack of books, one in particular, entitled The Book of Samael - A History of Silent Hill, caught his attention as he recovered from the fall. In addition to a glowing red symbol, the book also bore a byline with his name.
Whatley, finding Brenneman shortly after, made it clear to the journalist that authorship of that future book was now his responsibility, and placed the brand unto Brenneman's palm. Offering Brenneman the choice to leave Silent Hill and return to a world where people would think of his tales as nothing but ramblings of a madman, Whately explains that the mark would protect him from any and all harm, so he could freely fulfill his duty.
In addition to identifying those in the thrall of Samael, the Brand is, according to Whately, part of a language of symbols that is capable of opening doors between worlds.