RuneQuest

RuneQuest was created by Chaosium in 1978, making it one of the oldest tabletop Role Playing Games. Among other things, it introduced an experience system that replaces the levels (as in Dungeons and Dragons) with skills that increase if you successfully use them (Traveller replaced levels with skills first but they didn't increase with use). It also introduced hit regions instead of general Hit Points. The system was also used for other Chaosium games like Call of Cthulhu (tabletop game), Stormbringer, and the Elf Quest RPG, and was in 2004 developed into the generic BRP (Basic Role-Playing System).

The original RuneQuest was set in the Constructed World named Glorantha. As the authors say:

"Glorantha is an action-packed world of adventure. Gods and Goddesses struggle here, with nations of people nothing but their pawns. The stormy barbarians with their brutal but honest Storm God struggle against the Lunar Empire, led by the imperial Sun God and devious Moon Goddess.

Glorantha is an exciting world of heroes. Legends are being made by great individuals, many who are not even human beings. Some work with the deities, other heroes and heroines fight against them.

Glorantha is colorful and full of magic. Supernatural animals are found, ranging from unicorns to seven types of merfolk and the Goddess of Lions.

Glorantha is immense. If explored, it has different worlds and dimensions, whole realms where Gods, spirits and sorcerous powers come from. Unlike many fantasy settings, Glorantha emphasises religion, myth and belief to a level rarely seen in roleplaying or fantasy fiction elsewhere.

Glorantha shares some fantasy tropes such as dwarves, elves, trolls and giants, but has developed them differently to the more conventional versions based on the work of Tolkien. Dwarves are literally made of stone and exist as manifest rigid inflexible laws of creation, while elves are intelligent, mobile plants. Glorantha is full of surprises.

Glorantha is as deep as you want it to be, or not. Hackers and choppers have what they want, while scholars and mythologists have a vast playground of new stories, legends and myths to enjoy."

Glorantha is also the setting of the clan-developing computer game of The King of Dragon Pass.

Provides examples of:
 * A Protagonist Shall Lead Them: Argrath.
 * All Myths Are True: All Gloranthan myths are literally true, even utterly contradictory myths of different cultures. Changing a myth (by going on a Hero Quest to the world of the gods) can retroactively change reality.
 * Anthropomorphic Personification: The deities of the Celestial Court personify the Runes.
 * Assimilation Plot: The Empire of Wyrmfriends wants EVERYBODY to embrace their draconic nature. Later, the Lunar Empire also wants everybody to worship their Goddess, so that the world can be one again. And damn are they succeeding.
 * The Goddess was eventually defeated, but probably she is just hiding.
 * Bad Moon Rising: The Red Moon rose, and her Empire wants you to worship her.
 * Barbarian Tribe: The Orlanthi.
 * Big Bad: Sedenya/Lunar Goddess/Red Moon is this for the Orlanthi in the Third Era.
 * Big Bad Duumvirate: Wakboth and Kajabor in the Greater Darkness.
 * Chariot Race: Monster Coliseum has rules for chariot racing.
 * Chaos on Earth: The Greater Darkness.
 * Dark Is Not Evil coupled with Light Is Not Good: For humans, sure they are, but trolls are subterranean creatures; troll Hell is located in human Heaven and vice versa.
 * Also, the Sun God Yelm is evil to the followers of Orlanthi Storm Pantheon, but good to the followers of the Sun pantheon.
 * Even though Zorak Zoran and his worshippers are complete man-eating, necromancy-edged, brawl-loving berserks, other Troll gods are actually quite benevolent, if only a bit brutal. Well, they may still eat you, but only because they're hungry, nothing personal to it.
 * Dark Messiah / Messianic Archetype / The Antichrist: Nysalor/Gbaji, depending of the interpretation.
 * Deus Ex Homine: Zistor and Nysalor, who was to be the perfect deity.
 * Ear Wings: The chonchon.
 * Eldritch Abomination: The Lunar Goddess rides one of these.
 * Fantasy Gun Control: The dwarves have rifles. There is even a renegade Dwarf Cult of the Cannon in the Dragon Pass.
 * Fantasy Pantheon: Many.
 * Fauns and Satyrs: The Broos.
 * God Couple: Yelm and Dendara, Orlanth and Ernalda.
 * God-Emperor: The Red Emperor is this for the Lunar Empire.
 * God Is Dead: Orlanth killed Yelm and it ended badly. Luckily he got better, thanks to Orlanth's Redemption Quest.
 * God of Evil: Wakboth the Devil.
 * Grey and Gray Morality: A main staple of the setting, though Wakboth and the Unholy Trio are pitch black.
 * Hit Points: Averted. Hit points generally do not increase with experience. No matter how bad ass an adventurer is, an axe to their head will ruin their whole day.
 * Only a Flesh Wound: Generally averted, due to the hit-location system. Characters can get crippled very easily in combat.
 * Which goes under Subsystem Damage.
 * Armor Is Useless is likewise averted, as armor provides Damage Reduction. Heavy armor and a good shield are the best way to survive a battle.
 * Lovecraftian Superpower: Exposure to Primal Chaos can give you "Chaos Features", neat powers that often come with horrific physical manifestations. But you can also be Blessed with Suck and end up with "Chaos Flaws".
 * Love Goddess: Uleria.
 * Lunacy: In addition to the standard Earth, Air, Fire and Water elementals, Glorantha also has Darkness and Moon elementals. Moon Elementals cause temporary insanity by touch.
 * Mad God: Ragnaglar of the Unholy Trio.
 * Mythopoeia
 * Morally-Ambiguous Ducktorate: Beware, beware the Deadly Ducks of Death!
 * Order Versus Chaos: Lunar Empire versus Orlanthi, big time.
 * Kind of a weird case - the Lunar Empire promotes (cosmic) Chaos but is very organized, whereas the Orlanthi are Chaos-hating barbarian berzerkers.
 * Our Gods Are Greater: Goes without saying.
 * Our Monsters Are Different: You can even play intelligent ducks, called Durulzi in RuneQuest. (It has its advantages: small size, high Dexterity, and hardly anyone notices a Duck — perfect for a thief/rogue or a mage. And you know what? They have their own island empire in the far East.)
 * All Trolls Are Different: Among other things, they're matriarchial, cannibalistic, and Extreme Omnivores.
 * Our Dragons Are Different: True Dragons are beings of unfathomable power, and human beings can become dragons if they follow Draconic Mysticism. The Empire of Wyrmfriends wants to assimilate everybody into being dragons.
 * Our Elves Are Better: They're kind-of dryads, or Plant Aliens.
 * Our Dwarves Are All the Same: Massively averted. Dwarves are made into one of several castes, very different from each other. And they are not Viking-like, they are instead living tools dedicated to repairing the once-perfect World Machine.
 * Plaguemaster: Malia, the Mother of Disease.
 * Plant Person: The elves.
 * Pride: The God Learners thought that they could do whatever they wanted with those ridiculous pagan deities. Boy were they wrong.
 * Redemption Quest: Orlanth's To Hell and Back.
 * Spirit World: The Otherworld.
 * Supernatural Martial Arts: Mostly gained through Kralorelan mysticism, by monastic adepts who give in to temptations of power while ostensibly trying to Ascend to a Higher Plane of Existence (most of the students, frankly, are just there to try to reach the really good temptations).
 * Battle magic is something in between this and Full-Contact Magic.
 * The Archmage: Zzabur.
 * The Chosen One: Several, Argrath being one of the main examples.
 * The Empire: The Lunar Empire.
 * The Maker: The Maker of the Mostali (dwarves).
 * The Night That Never Ends: This is what happens when you kill the Sun God. And then it gets worse.
 * To Hell and Back: The Lightbringers, to rescue Yelm and end the Greater Darkness.
 * Top God: Many pantheons have one, but Sedenya, Yelm and Orlanth are the most important. Arachne Solara can be seen as a Goddess of Gods.
 * Trickster Archetype: Several.
 * War God: Several.
 * Weird Moon: Glorantha has never had a conventional Earthlike moon. The Blue Moon is tiny and rarely visible save as a streak of light, whereas the Red Moon is of recent vintage, ripped from the middle of Dara Happa, and hovers in place over the Lunar Empire, revolving to show a red side and a black side. It is said that a White Moon may rise someday.