Colin's comments: This document details the various official deities appropriate to the monsters (but not demihumans) presented in the Monster Manual. I felt that the scant information provided in the Monster Manual (a name, and the domains) failed to really enable the DM to effectively utilize monstrous clerics in a 3rd edition campaign. This is a notable problem for those DMs and players new to Dungeons & Dragons, as well as those returnees, like myself, who lack the existing back catalogue and knowledge longstanding players would have. Each of these entries presents the name of the deity, a list of the areas of life (or death) the deity is responsible for, their appearance, domains, favored weapon, and symbol. This information has been converted from the long out of print Monster Mythology supplement, but does not cover deities of monsters not presented in the new Monster Manual. Additionally, it does not provide the in-depth histories/mythologies, character conflicts, and avatar information presented in that supplement, or the details of those deities that don't have priesthoods.
In all cases the domains are identical to those presented in the new Players Handbook, Monster Manual, and Forgotten Realms Guidelines, with only a handful of logical changes. For example, I added the Cavern domain (from the Forgotten Realms Guidelines) to Kurtulmak, the chief kobold deity, to represent his patronage of mining, while removing his Luck domain (because, as anyone who has read Monster Mythology could tell you, Kurtulmak is perhaps the unluckiest deity there is!). Similarly, Merrshaulk, the yuan-ti deity was listed with the Plant domain in the Monster Manual, when he has nothing to do with plants, and everything to do with reptiles (so I added the Scalykind domain). The Monster Manual (and Players Handbook) were not written with the benefit of all the extra domains presented in the Forgotten Realms Guidelines, whereas I was able to make good use of them in this piece.
Needless to say, this piece will eventually be superseded by an official supplement of some kind, but it should suffice until that point. Should there be enough interest, I'm working up a similar treatment of the demihuman deities (dwarves, elves, gnomes, halflings, and drow), using the same sources, as well as the old Demihuman Deities supplement for the Forgotten Realms. Any comments, suggestions, thanks, and donations of money should be directed to me at: thystram@moonpie.fsnet.co.uk
Hope you enjoy this!

                                                                   Bugbear
Hruggek
Hruggek is the master of the bugbear pantheon. A master of savage conflict, ambush, and cunning, he is a powerfully muscular bugbear with over-sized fangs and claws, wielding a vast, two-handed morningstar. His domains are Chaos, Evil, Trickery, and War. His favored weapon is the morningstar. His symbol is the morningstar.

Grankhul
Grankhul is chaotic evil. He governs hunting, vigilance, and surprise, and taught the bugbears the value of stealth. A lean bugbear with bulging eyes, his long slender fingers wield a longsword. His domains are Chaos, Evil, and Trickery. His favored weapon is the longsword. His symbol is a pair of ever-open eyes in darkness.

                                                                   CENTAUR
Skerrit
Skerrit is neutral good. He oversees the community, and natural balance, and is concerned with protection, and hunting. He is depicted as a powerful male centaur with chestnut hair, a chainmail vest, golden-tipped spear and longbow. His domains are Animal, Good, and Plant. His favored weapon is the spear. His symbol is an oak growing from an acorn.

                                                         Giant, Cloud
Stronmaus
Stronmaus is neutral good, and is worshipped by good cloud giants, and storm giants. He governs the sun, skies, and weather, and is a vibrant, dramatic, and muscular giant with laughing blue eyes, flowing red hair, a gold-trimmed white robe, magnificent hammer, and perpetual smile. His domains are Good, Storms, Strength, and Sun. His favored weapon is the hammer. His symbol is a lightning bolt descending from a silver-lined cloud partially obscuring the sun.

Memnor
Memnor is neutral evil, and is worshipped by evil cloud giants. Patron of pride and domination, he is subtle, cultured, prideful, and intelligent. He is depicted as a kindly-looking, golden-hued cloud giant with a piercing gaze, deep blue robe, and morningstar. His domains are Charm, Evil, and Trickery. His favored weapon is the morningstar. His symbol is a black obelisk.

                                                              GIANT, FIRE
Surtr
Surtr is lawful evil. He is the aggressive and tyrannical patron of fire giants. He is depicted as a huge, powerful fire giant with real flames for hair, bearing a flame-wreathed black greatsword, and chainmail that glows red with heat. His domains are Evil, Fire, Law, and War. His favored weapon is the greatsword. His symbol is a flaming sword.

                                                          GIANT, FROST
Thrym
Thrym is chaotic evil. He is the master of all frost giants, promoting violence and savagery. He is depicted as a huge frost giant with icicles in his white hair and beard, wearing chainmail and bearing a huge white greataxe. His domains are Chaos, Destruction, Evil, and War. His favored weapon is the battleaxe. His symbol is a white double-headed axe.

                                                GIANT, HILL/ETTIN
Grolantor
Grolantor is chaotic evil. He is strong and aggressive but stupid and cowardly at times, and is worshipped by hill giants and some ettins and ogres. He is a huge hill giant bearing an over-sized club. His domains are Chaos, Destruction, Evil, and Strength. His favored weapon is a club. His symbol is a wooden club.

                                                          GIANT, STONE
Skoraeus Stonebones
Skoraeus Stonebones is neutral, and is the god of stone giants. A bastion of the earth, he is dour, and stoic, with granite skin and a stalactite club. His domains are Cavern, Earth, and Strength. His favored weapon is the club. His symbol is a stalactite.

                                                                        GNOLL
Yeenoghu
Yeenoghu is chaotic evil. A powerful tanar'ri, he has risen to become the patron of gnolls, and has strong ties with cannibalism and the undead. He is depicted as a skeletal, furless gnoll, with only a many crest of yellow fur, and a three-headed flail. His domains are Chaos, Death, Destruction, and Evil. His favored weapon is the flail. His symbol is a triple-headed flail.

                                            Goblin/Hobgoblin
Maglubiyet
Ruler of the goblin/hobgoblin pantheon, Maglubiyet is patron of aggression, war, and rulership. He is a massive goblin with skin like pitch, and eyes of crimson flame, bearing a coal-black axe dripping with gore. His domains are Destruction, Evil, and Trickery. His favored weapon is the battleaxe. His symbol is a bloody axe.

Khurgorbaeyag
Khurgorbaeyag is neutral evil. The specific patron of goblins, he is the master of slavery and oppression, depicted as a red-skinned goblin speckled with yellow and orange scales, carrying a whip and wearing scale mail. His domains are Evil, Suffering, and Trickery. His favored weapon is the mace; the whip is used as a symbol only. He is the most trusted of Maglubiyet's most trusted follower, which is not really saying very much. His symbol is a red and yellow striped whip.

Nomog-Geaya
Nomog-Geaya is lawful evil, and is the specific patron of hobgoblins. He espouses stoicism, courage, ruthlessness, conflict, and authority, and is a powerful hobgoblin with ashen skin, chilling orange eyes, and shark-like teeth, bearing a longsword in one hand and a hand axe in the other. His domains are Evil, Law, and War. His favored weapon is the longsword or hand axe. He disdains Bargrivyek as a coward. His symbol is a crossed sword and axe.

Bargrivyek
Bargrivyek is lawful evil. He promotes cooperation between goblin/hobgoblin tribes in order to concentrate on further expanding territory. He is depicted as a large goblin with a domed forehead, calm mien, and white-tipped flail. His domains are Evil, and Law. His favored weapon is the flail. He fears Maglubiyet and Nomog-Geaya. His symbol is a white-tipped flail.

                                                                     Kobold
Kurtulmak
Hateful, gloating, and humorless, Kurtulmak is the chief kobold god. He governs war and mining, and is a large kobold with a sinuous stingered tail, large horns, black and green scales, and a wickedly-tipped spear. His domains are Cavern, Evil, Law, and Trickery. His favored weapon is the spear. His symbol is a gnome skull, his clerics wearing orange robes that prominently display this symbol on the chest.

Gaknulak
Gaknulak is lawful evil. Sneaky and pragmatic, he embodies protection, stealth, trickery, and traps. He is a small dark kobold with bulging pockets, a hand axe, and a magical cauldron from which tools and unpredictable minor magical items may be pulled. His domains are Evil, Law, Protection, and Trickery. His favored weapon is the hand axe. His symbol is a cauldron.

                                                                   KUO-TOA
Blibdoolpoolp
Blibdoolpoolp is neutral evil. She is depicted as a naked female human with the head and pincers of a lobster. Her domains are Destruction, Evil, and Water. Her favored weapon is the pincer staff. Her symbols are a lobster head and a black pearl.

                                                           LIZARDFOLK
Semuanya
Semuanya is neutral. He is entirely amoral, concerned only with the survival of the lizardfolk, and is depicted as a large lizardman with a shell-encrusted club. His domains are Plant, Scalykind, and Water. His favored weapon is the club. His symbol is an egg.

                                                     LOCATHAH/MER
Eadro
Eadro is neutral, and is the creator of the locathah and mer races, although both races assert they were the most perfect of the two creations. He is aloof, and enforces the traditional values of his races' societies. He appears as a tall merman or locathah. His domains are Animal, Protection, and Water. His favored weapon is the spear or trident. His symbol is a spiral.

                                                                MINOTAUR
Baphomet
Baphomet is chaotic evil. A vile, bloodthirsty, bull-headed ogre, Baphomet is obsessed with battle, and wields a mighty bardiche. His domains are Chaos, Evil, and War. His favored weapon is the bardiche. He is in continual conflict with Yeenoghu. His symbol is a maze.

                                                                          OGRE
Vaprak
Vaprak is chaotic evil. Commonly called The Destroyer, Vaprak is rapacious, greedy, violent, and frenzied, a foul brown-green ogre with taloned hands and a vicious club. His domains are Chaos, Evil, and Destruction. His favored weapon is the club. He fears his followers will desert him in favor of the giant gods. His symbol is a taloned claw.

                                                                             Orc
Gruumsh
Leader of the orc pantheon, Gruumsh is typically depicted as a scarred, cyclopean orc, clad in ebony full plate, bearing a great spear and flaming torch. His domains are Chaos, Evil, Strength, and War. His favored weapon is the spear. His symbol is a single unblinking eye.

Bahgtru
Bahgtru, son of Gruumsh and Luthic, is chaotic evil. He is a brutally strong deity, and brutally stupid deity, depicted as a vastly muscular orc with filthy skin, dull eyes, over-sized tusks, studded leather armor, and heavy gauntlets. His domains are Chaos, Evil, and Strength, and the only weapons he favors are gauntlets. He scorns heavy armor. Although loyal to Gruumsh, his first loyalty is to Luthic. His symbol is a broken thigh bone.

Ilneval
Ilneval is Gruumsh's lieutenant and battle leader, and is chaotic evil. A looming, grim orc clad in blood-red chainmail, and armed with a longsword, Ilneval is ferocious, and demonstrates the strength of leadership from the front. His domains are Chaos, Evil, and War. His favored weapon is the longsword. He secretly covets Gruumsh's position, and Gruumsh does not entirely trust him. His symbol is a bloodied sword.

Luthic
Consort to Gruumsh, and mother of Bahgtru, Luthic is chaotic evil. A female orc with black blaws, hair and eyes, she is representative of the subservience of female orcs, and is associated with female fertility, healing, and caverns and caves. Her domains are Cavern, Chaos, Evil, and Healing. She has no favored weapon. She is loyal to Gruumsh, but is extremely close to her son, Bahgtru. Her symbol is a cave entrance.

Shargass
Shargass is chaotic evil. Also known as The Nightlord, he is cunning and cold-blooded, associated with darkness, stealth, and thievery. A gaunt and leering orc, he has black skin and eyes, and is always enfolded in a voluminous black cloak. His domains are Chaos, Evil, and Trickery. His favored weapon is the quarterstaff. His symbol is a red crescent moon with a skull between the moon's horns.

Yurtrus
Yurtrus is chaotic evil. Also called White-Hands, Yurtrus is greatly feared, for he is the bringer of death and disease, a vast orc covered with tattered, putrescent green flesh, devoid of mouth, and with perfect bone-white hands. His domains are Chaos, Death, Evil, and Suffering. His favored weapon is the mace, its head shaped like a white fist. His priests wear gloves of pale white humanoid skin, and leather armor/garments of the same material. His symbol is a white hand on a dark background.

                                                                 SAHUAGIN
Sekolah
Sekolah is lawful evil. A ruthless, ever-hungry, and uncaring massive white shark, Sekolah urges the Sahuagin to plunder, hunt, and dominate. His domains are Evil, Law, Strength, and War. His favored weapon is the trident. His symbol is a white shark.

                                                                       TRITON
Persana
Persana is neutral. He created the tritons out of the enchanted water from the elemental plane of water. He is depicted as a muscular triton with emerald skin, a large pink conch, sharkskin armor, and a trident. His domains are Protection, and Water. His favored weapon is the trident. His symbol is the trident and conch.

                                                          TROGLODYTE
Laogzed
Laogzed is chaotic evil. He is depicted as a huge toad/lizard cross, with pustulent loose skin, and seems to have little interest in anything beyond devouring whatever is unfortunate to cross his path. His domains are Chaos, Death, Destruction, and Evil. His favored weapon is the javelin. His symbol is a lizard's head.

                                                                     YUAN-TI
Merrshaulk
Merrshaulk is chaotic evil. He is associated with poison and somnolence, and is depicted as a powerful yuan-ti abomination with a male human's head, stubby forearms and a pair of scimitars. Only yuan-ti abominations may be his clerics. His domains are Chaos, Destruction, Evil, and Scalykind. His favored weapon is the scimitar. His symbol is a cobra's head.

                                                                  WERERAT
Squerrik
Squerrik is lawful evil. Patron of the wererats, he promotes stealth, and thievery, and is depicted as a fearful ratman in grimy leathers, bearing a shortsword. His domains are Evil, Law, and Trickery. His favored weapon is the shortsword. His symbol is a rat's head with bared yellow teeth.