"The Right Hand of Doom" is my favourite very short Kane story by Howard. This in spite of its having such a well-used theme, the severed hand that carries out grim deeds either at the will of its owner or by itself. "The Beast With Five Fingers" and "The Hands of Orlac" come to mind.
The yarn has punch precisely because it's so short. And the personality and character of Kane come across vividly in his exchange with the treacherous John Redly, as Redly boasts of having earned a reward from the law by turning in a magician. He asks Kane what he thinks of that. Kane stares at him coldly and answers that Redly has done a damnable deed. "Yon necromancer was worthy of death, belike, but he trusted you, naming you his one friend, and you betrayed him for a few filthy coins ... you will meet him in hell, one day."
A fine little story that WEIRD TALES inexplicably rejected! It poses an interesting conundrum. The loathsome John Redly says the necromancer Simeon was arrested by "the king's soldiers." Yet it's generally accepted that Solomon's adventures occurred during the era of Queen Elizabeth I, as established in some of the other stories and poems. There's probably a mundane explanation; namely, that the setting was still nebulous in Howard's mind at this early stage of the series. Or, if Howard already envisioned an Elizabethan backdrop, it was simply a slip of the typewriter. In the spirit of the game, I've suggested that "the king" was Elizabeth's half-brother and predecessor Edward VI. This squares with Glenn Lord's placement of "Right Hand" very early in Kane's career. Other fans have reasonably argued that it's difficult to reconcile a 1550s date with the much later Elizabethan backdrop in other stories. Still, that's half the fun with Howard, elaborating on details that he liked to toss off as bones that we fans are left to pick up and chew on.
I've a notion, myself, that "The Right Hand of Doom" in which Kane is a witness to events, not a fierce fighting protagonist, took place late in his life, just before the poem "Solonon Kane's Homecoming", and the "king" John Redly mentions was Elizabeth I's successor James.