This article is a list of creatures in the Infocom text adventure Zork universe.
:See also: Characters in Zork, Items in Zork, Kings of Quendor, and Zork timeline.

B

;Bloodhound
Bloodhounds were a favorite of Dimwit Flathead, who maintained a collection of them in the Royal Kennels and reportedly based the bloit on them (a bloit was determined by the distance that the King's favorite pet could run in a set period of time).
;Bloodworm
Bloodworms live in the Miznia Jungle and can be mistaken for "mossy rocks".
;Brogmoid
Brogmoids are dimwitted giant humanoid creatures. The oft-ridiculed beliefs of Brogmoidism hold that a giant Brogmoid holds up the Earth and that another giant Brogmoid standing on the Earth holds up another world. These beliefs are verified by the adventurer in Zork Zero. However, the similar Turtle Theory put forward by Leonardo Flathead remained the popularly accepted explanation.

C

;Cerberus
Cerberus guards the Tomb of the Twelve Flatheads in Zork II but can be tamed with a collar.
;Christmas Tree Monster
Christmas Tree Monsters are cold-weather plants who migrate in the autumn with disastrous results. They fear caterpillars. A herd of them threatened Thriff village in Beyond Zork. Orkan the enchanter held them at bay with a Glyph made of ice until a volcanic eruption destroyed most of them and created a permanent Glyph.
;Cruel Puppet
Encountered in Beyond Zork, the Cruel Puppet reduces the endurance of adventurers by mocking them with words or shapeshifting. Can only be destroyed by magic or a combination of luck and high stats.

D

;Discipline Crab
Encountered in the Cellar of The Rusty Lantern in Grubbo-by-the-Sea in Beyond Zork, Discipline Crabs are a particular territorial breed of crab which hoards valuables hidden in debris.
;Dust Bunny
Encountered in the Lighthouse of Grubbo-by-the Sea in Beyond Zork, Dust Bunnies multiply like rabbits via agamogenesis but can be dispelled by static electricity.

E

;Eldritch Vapors
Encountered in Grubbo-by-the-Sea in Beyond Zork, Eldrich Vapors filch items, depositing them in random nearby locations. They cannot steal items which are wielded or stored in a pack.
;Elves
Elves are not encountered in the Zork universe, but there is an "elvish sword of great antiquity".

F

;Flamingo
Encountered in Zork Zero, the cannot be captured in the Garden Room. However, the Flamingo can be transfigured using the Wand and used in the Laboratory, in conjunction with the Flamingo food to cure the hunger curse.
;Fungus
Encountered in Zork Zero, Fungi are a parasite inhabiting Brogmoid ear wax and toe fungus which can be communicated to using a potion invented by Thomas Alva Flathead.

G

;Giant Bat
These large bats amuse themselves by grabbing adventurers and depositing them somewhere completely different.
;Giant Corbie
Giant Corbies are huge birds encountered in the Fields of Frotzen in Beyond Zork with extremely sharp color vision and very specific fears of colors.
;Giant Slug
Encountered in the Lighthouse of Grubbo-by-the-Sea in Beyond Zork, the giant slug can easily be defeated by throwing salt from the patch of brine at it.
;Giant Spiders
;Grue
;Glurz
Glurz is a species of fish encountred in Beyond Zork which can be eaten fried bestowing increases in intelligence.
;Gnome
Gnomes were employed exclusively by J. Pierpont Flathead to work in the Bank of Zork for reasons which remain unknown. There is also a mention of Gnomes working on the Great Underground Highway, but the toolbooth is unmanned when encountered in Zork Zero.
;Gnome of Zurich
Lets the adventurer out of the Small Room (in the Bank) if the way back is closed in exchange for a valuable object. Other objects he crushes in his "rock-hard" hands. Since another he will accept is necessary to win, you can't complete the game if you see him.
;Guttersnipe
A bird of prey encountered in Grubbo-by-the-Sea in Beyond Zork.

H

;Hellhound
Encountered in the forest in Beyond Zork, a Hellhound is a generic, although difficult to defeat, monster.
;Hungus
A Hungus is a permutation of a sheep and a hippopotamus found in the Miznia Jungle in Beyond Zork which is integral to solving the Crocodile's Tear puzzle.

J

;Jeearr

L

;Lucksucker
Lucksuckers are shapeshifting monsters found in the Ur-grue's cave in Beyond Zork. To defeat the three lucksuckers the adventurer must throw a good luck charm at each of them (The three good luck charms found in the game are: the rabbit's foot, the horseshoe, and four leaf clover).

M

;Minx
The Minx is an irresistably cute combination of a cat, a pig, and a koala bear which can dig for truffles. It is integral to finding the Helmet in Beyond Zork.

N

;Nymph
Nymps are small, annoying, fairy-like, servile creatures in Beyond Zork such as the warning nymph and the financial nymph. They pop up to give you information which may or may not be helpful.

O

;Otto
Otto is John Paul Flathead's pet toad who will only turn over the Spyglass if given three flies and called by his name in Zork Zero.

O

;Platypus

R

;Rat-ant
Encountered in the cellar of The Rusty Lantern in Grubbo-by-the-Sea in Beyond Zork.
;Roc
Encountered randomly On the Lake in Zork III, the Roc can eat adventurers although it is little more than a rare easter egg.

S

;Sea Serpent
Encountered in the Aquarium Room in Zork II as the Wizard of Frobozz's pet, the Sea Serpent guards the clear Orb. It will kill the adventurer if one reaches into the aquarium or breaks it with a suboptimal object. It can only be defeated by throwing the Bat or Sword at the aquarium or by saving the water absorbing cake from the Tea Room. In Version 7 of Zork II, you can tell it to do things after it dies with commands like:

TELL SERPENT "E THEN LOOK"

T

;Toad
See Otto
;Troll

U

;Ur-grue
;Unicorn
Encountered in Zork II the Unicorn can only be captured by the Princess, who thereupon gives the Gold Key on its neck to the adventurer. In Beyond Zork it is discovered that there is a Unicorn society in another plane of existence which can be accessed through an old sea chest.

W

;Windcat
The favorite pet of Bozbo IV who made for a very large bloit measure.

V

;Vampire Bats
Vampire Bats inhabit the Bat Room in Zork I and are repulsed by Garlic.
;Volcano Gnome
Like the Gnome of Zurich, he lets the adventurer out of the volcano for a valuable object if the balloon floats out of the volcano.