Bugs, Amphibians and the Rise of Giants

The Carboniferous forest does not resemble any woodland of the campaign present.

There is no grass beneath the canopy. No flowers brighten the mud. No birds sing above it.

Instead, towering lycopsids, calamites, ferns and seed plants form dense green walls around flooded ground. Dead vegetation sinks into waterlogged earth. Over immense spans of time these buried forests become the coal seams opened by miners hundreds of millions of years later.

Arthropleura beneath the trees

The most imposing traveller on the forest floor is Arthropleura.

Its segmented armour moves between tree roots and fallen trunks in a long ripple of plates. The largest individuals are longer than a man is tall. Their broad tracks cross mudbanks, vanish beneath litter and emerge again beside black pools.

They are not the only giants.

Over the open water hunt enormous griffinflies, represented in the SpiralWorlds Bestiary by the Giant Dragonfly. Their wings cut through the heavy forest air as they pursue smaller insects above stagnant channels and drowned margins.

Something moves in the black water

The waterways are no safer than the forest floor.

Large tetrapods patrol pools, channels and drowned forest margins. Among them is Eogyrinus, a long-bodied ambush hunter at home in slow Carboniferous water.

A traveller might first notice only a wake beneath floating vegetation.

Then the broad skull rises.

These creatures are often called amphibians for convenience, but this is no kingdom of oversized modern frogs. The Carboniferous is filled with extinct forms unlike anything a later natural philosopher will see alive.

The creatures that leave the swamp

The decisive change begins quietly.

Some small tetrapods can reproduce without returning their eggs to open water. That freedom matters more than armour, teeth or size.

Their descendants push beyond wetland margins into woodland, uplands and seasonally dry country. From those pioneers will eventually come both the mammal-line beasts of the Permian and the reptilian dynasties of the Mesozoic.

The Father of Serpents watches

Much later, the oldest cults of Yig remember this expansion as the first great serpent-marking of the land.

The claim is not that Yig invents reptiles from nothing. Natural lineages are already diversifying across Earth.

Serpent tradition instead claims that the Father of Serpents recognises certain bloodlines, favours them, alters some and begins a relationship with scaled life that will outlast continents.

The wars no fossil records

Even these immense forests are young compared with some of the beings already present.

Elder chronicles place renewed activity by Cthulhu within this age.

His Star-Spawn contend with the ancient Elder Things in wars fought across coastlines and ocean basins that no longer exist.

The cyclopean city later remembered as R’lyeh belongs to these traditions: not a modern Pacific island somehow transported into deep time, but an elder territory on a planet whose geography will be remade again and again.

The green empire breaks

The great wet forests do not last forever.

Ice advances and retreats across southern Gondwana. Sea levels shift. Climate becomes more seasonal. Once-continuous forests fragment into separated refuges.

The giant arthropods remain. The river hunters remain.

But the world around them is becoming drier.

The swamp has begun to lose its crown.

The Permian opens beneath a harsher sky.

Pangaea is becoming a single immense landmass. Far from the oceans, its interior grows seasonal and dry. Wetlands still follow rivers and lakes, but between them stretch open woodlands, floodplains and increasingly arid country.

For the creatures of the old swamp world, water becomes territory worth defending.

River monsters

Large temnospondyls wait in channels and lake margins, some with skulls broad enough to resemble living traps.

They are among the last great heirs of an age when amphibious tetrapods were the foremost vertebrate predators of the wetlands.

The rivers remain theirs.

The dry land does not.

The hunters beyond the water

Synapsids spread through country where dependence on permanent water would be a weakness.

The sail-backed Dimetrodon is one of the most famous, though it is no dinosaur.

Another formidable predator is Sphenacodon, a deep-skulled hunter built for power rather than spectacle.

Elsewhere, heavily built herbivores browse through dry vegetation while later therapsid predators pursue them across floodplains and scrub.

The distant ancestors of mammals are already here, though nothing in their world yet resembles the mammalian dominion of later ages.

The spiral-jawed hunter

At sea, strangeness takes another form.

Helicoprion hunts with a remarkable spiral whorl of teeth set within its lower jaw.

No curse shaped it. No wizard designed it.

The creature is simply one of the many forms natural life has tried and later abandoned.

In SpiralWorlds, the natural world is often strange enough to require no enchantment.

Valusia before mankind

Across the Permian land rise kingdoms whose ruins no human civilisation will ever see newly built.

The Serpent People preserve traditions of an ancient realm later remembered under the name Valusia.

Its cities stand upon a version of Earth almost beyond later recognition: Pangaea united, unfamiliar mountain chains, vanished seas and no human beings anywhere upon the world.

Serpent priests serve old gods. Dynasties map bloodlines across generations. Underground sanctuaries descend beneath territories already ancient by the standards of the Permian.

Later serpent realms reuse ancestral names and claims. Valusia is therefore not one unchanged political state persisting intact for hundreds of millions of years, but a name carried forward through successive serpent dynasties and traditions.

The heat comes

Toward the end of the Permian, the world begins to fail.

Volcanism spreads across what will one day become Siberia. Heat builds. Weather patterns become unstable. Oceans warm.

The first losses can still be mistaken for bad years.

Then whole ecosystems begin to disappear.

The first Triassic landscapes are sparse.

There are places where a traveller can cross miles of harsh ground and see only a handful of common survivors.

The most famous is Lystrosaurus: a squat, tusked herbivore so successful in the devastated world that its bones dominate some Early Triassic landscapes.

Temnospondyls still haunt rivers. Cynodonts remain small but persistent. The surviving world is battered, repetitive and dangerous.

Then diversity begins to return.

The archosaur world

The Triassic becomes an age of strange experiments.

Armoured Stagonolepis cross the land in heavy coats of scutes.

Elsewhere, Postosuchus stalks the open country.

Despite the legacy directory path of its Bestiary page, Postosuchus is not a dinosaur. It is one of the great crocodile-line archosaurs: a powerful terrestrial predator living in the same world where the first dinosaurs are still only one group among many.

This matters because the early dinosaurs do not inherit an empty continent.

They must survive monsters already there.

The dinosaurs arrive

The first definite dinosaurs appear during the Triassic.

At first many are small, agile animals sharing the land with predators that can kill them, armoured herbivores they cannot easily attack and amphibious hunters still dominating the rivers.

Later forms begin to grow.

Plateosaurus walks the Late Triassic landscape as a substantial herbivore, its long neck and heavy body foreshadowing the far greater long-necked giants of the Jurassic.

The dinosaur age has begun.

It simply has not won yet.

Wings over Pangaea

Then a vertebrate leaves the ground under its own power.

Pterosaurs stretch membranous wings between elongated fingers and body. They are neither birds nor dinosaurs.

For the first time, the skies contain vertebrate flyers.

Below them, giant insects are no longer unmatched rulers of the air.

Giants beneath the sea

The recovering oceans produce monsters of their own.

Ichthyosaurs become fully marine hunters, some reaching enormous size.

Among them is Shonisaurus, a creature large enough to turn an encounter at sea into the sighting of a moving island.

The oceans have recovered enough to support giants once more.

The small creatures no one fears

In the shadows of all these reptiles, small cynodont descendants continue changing.

Some become early mammaliaforms.

They are not rulers. They are not giants. Most great predators barely notice them.

That obscurity becomes their defence.

Long after the great archosaurs have fallen, their descendants will still be here.

The rains return

The Triassic is often dry, but not always.

During the Carnian, rain returns on a vast scale. Rivers swell. Vegetation changes. Old communities are disrupted again.

Through the ecological upheaval, dinosaur lineages gain ground.

The strange survivor world is becoming a dinosaur world.

The servants rebel

Below the surface, another ancient order is failing.

The Elder Things once created Shoggoths as servants.

In the early Triassic, with Elder Thing power already weakened by planetary catastrophe, the servants rise against their makers.

The revolt spreads through hidden complexes and ancient colonies.

Some Shoggoths are destroyed.

Others escape.

Some are never found.

The rebellion is not the cause of the Great Dying. It is something more dangerous: an ancient war exploiting a world already broken.

The serpent realms retreat

The Serpent People survive as well.

But their old surface dominions do not simply recover.

Dynasties fracture. Cities are abandoned. Refuge kingdoms move below ground. Later serpent chronicles remember another great political collapse around 225 million years ago.

From this point onward, serpent civilisation increasingly becomes a civilisation of hidden survival, forbidden archives and repeated attempts to reclaim what was lost.

The second extinction

Near 201 million years ago, the Triassic ends in another planetary crisis.

Volcanism associated with the opening central Atlantic drives rapid environmental change.

Many of the great archosaur rivals of the dinosaurs disappear.

Large amphibious lineages are reduced.

Marine communities suffer again.

Dinosaurs survive.

Pterosaurs survive.

Crocodile-line archosaurs survive.

Mammal-line animals survive.

But the balance has shifted.

The greatest terrestrial competitors of the dinosaurs are gone.

The Jurassic waits on the other side.