The Master of Monster Descriptions

Zelazny does not get enough attention in general in RPG circles, but in particular for his excellent, efficient descriptions of monsters. He may be the single most influential author on me in that regard. Some examples:

It looked like something that had started out to be a man but had never quite made it. It had been stepped on, twisted, had holes poked into the sickly dough of its head-bulge. Bones showed through the transparent flesh of its torso and its short legs were as thick as trees, terminating in disk-shaped pads from which dozens of long toes hung like roots or worms. its arms were longer than its entire body. it was a crushed slug, a thing that had been frozen and thawed before it was fully baked. (The Borshin, from Jack of Shadows)

There was something unusual about their appearance... For one thing, all had uniformly bloodshot eyes. Very, very bloodshot eyes. With them, though, the condition seemed normal. For another, all had an extra joint to each finger and thumb, and sharp, forward-curving spurs on the backs of their hands. All of them had prominent jaws (and) forty-four teeth, most of them longer than human teeth, and several looking to be much sharper. Their flesh was grayish and hard and shiny. There were undoubtedly other differences also, but those were sufficient to prove a point of some sort. (The shadow creatures of Fiona, from Nine Princes in Amber)

Morgenstern was six hands higher than any other horse I had ever seen, and his eyes were the dead color of a Weimaraner dog's and his coat was all gray and his hooves looked like polished steel. (Morgenstern, from Nine Princes in Amber)

Head something like a croc's, only bigger. Around forty feet long. Able to roll itself into a big beachball with teeth. Fast on land or in water - and a hell of a lot of little legs on each side. (The Boadile, from This Immortal)

Her hair was green, though streaked with silver, and her eyes were round of moons of jade and her brows rose like the wings of olive gulls. Her mouth was small, her chin was small; her cheeks were high and wide and rounded. A circlet of white gold crossed her brow and there was a crystal necklace about her neck. At its tip there flashed a sapphire between her sweet bare breasts, whose nipples were also bare green. She wore scaled trunks of blue and a silver belt, and she held a scepter of pink coral in her hand and had a ring upon every finger, and each ring had a stone of a different blue within it. She did not smile... (Moire, Queen of Rebma, from Nine Princes in Amber)

It's the little things, really, that do it: the careful but frequent reference to vivid colours and simple adjectives (shiny, dead, sweet, sickly); the arch observations ("a thing that had been frozen and thawed before it was fully baked"); and the wry humour ("there was something unusual about their appearance"). But it's very clever and incisive use of language, too - there's so much communicated in that very simple last sentence: "She did not smile."

Above all, what I like is that Zelazny is very comfortable with you, the reader, not having a clear picture in your head of what the monster is like - not so that you fill in the gaps yourself, so much as that you are given an impression in the artistic sense: a replication of what it would be like to encounter the thing being described. If you came across Morgenstern you wouldn't be jotting down every detail of his appearance. You'd notice the size, the eyes, the hooves - and then you'd run, or look away, or hide, or do something else. Capturing that in text is what Zelazny does at his best.