This is one of my favorite George R. R. Martin short stories/novellas. It’s done in the style of a typical Twilight Zone episode, which is no coincidence as Martin worked on an iteration of that show as well. What really sells the story for me is the concept of the Sandkings. As much as I love seeing the main character punished for all his cruelty, I was just as interested to see how the Sandkings would develop. It’s cliched, but I love stories where the real “monster” isn’t the monster.
With that said, the writing is very on-the-nose, and the twists are predictable.