Tyrrell is an Earth-like moon orbiting a gas giant, tentatively called 'Sister'. Tyrrell is roughly 3/4 the size of the Earth with slightly less gravity. It is a non-tectonic world that allows for very different and extreme geological features, comparable to those found on Mars. Sister and Tyrrell rotate around their sun in an annual orbit of 1440 days.  

Tyrrell lies within the solar system often called "Mother's Children"

Shorter-lived races such as Humans use the Siblings Calendar. A “solar year” is 1440 days, a “year” or aspect is 360 days, a month is 30 days, and a day is 24 hours. The “present day” in which most of the setting takes place is around Year 40 of the Third Age. The Third Age began with year 0 being in the 2914th year of the Second Age when the War of the Dawn started, the conflict between the Elderkin and the newly industrialized nation of Voskgardia. 

Tyrrell is home to several sentient species or races. They are usually classified into two groups, the Elderkin and the Lesserkin. The Elderkin are races naturally proficient in magic and who’s lifespan typically spans multiple centuries. The Lesserkin in contrast have little if any proficiency in magic and far shorter lifespans. 

Elderkin Races: 

Elves: The most numerous of the Elderkin. Tall, lithe, and with pointed ears, Elves can live close to 700 years, with some reaching their 1000th. They value living in harmony with nature and are among the most proficient magic wielders. Throughout the Second Age they were arguably the most dominant race in Tyrrell. However their power gave rise to complacency, and most Elves now lag far behind other races technologically. 

Dwarf: Short and stocky Elderkin famous for their mining and craftsmanship. Dwarves typically, though not exclusively, live in subterranean cities beneath mountains. Many Dwarvish holds and nations have been historically very wealthy. Though a century or so behind the innovations of Humanity, Dwarven technology is built to the highest possible level of craftsmanship and is enhanced through Runic magic. 

Cyclopes: These one-eyed muscular giants typically stand around four meters tall. Cyclopes societies place a heavy emphasis on strengthening one’s body and mind. As a result they have some of Tyrrell’s greatest philosophers and mathematicians. Most Cyclopes live on the continent of Elysia, with independent Cyclopes countries rarely found elsewhere. 

Lesserkin Races: 

Human: Originally primitive tribes, Humans began developing countries on the edge of Elderkin nations. Humans are universally feeble in the art of magic, unable to utilize it in most practical ways. They were at the mercy of the Elderkin for millennia. However thanks to industrialization Humans are now the most technologically developed species in Tyrrell, rapidly upending the global balance of power.  

Orc: Orcs are the green-skinned natives of the Red Steppes in East Ciradon. Often stereotyped as fierce warriors, Orcs became infamous for their conquests during the Orcish Invasions. Wooly Rhinos are of great importance to Orc culture and taming one grants prestige. Rhino riders form the upper class of Orcish society. The majority of Orcish armies are foot-based, using spears, swords, or longbows. 

Goblin: Goblins are a subspecies of Orc originating from a group of islands to the northwest of the Red Steppes. They are significantly smaller than their kin, have a seafaring culture, and are organized into a collection of city-states.

Beastkin: While not a singular race, what this diverse collection of species has in common is that they resemble half-human, half-animal hybrids. Examples include Centaurs, Minotaurs, Lyncans, Felenids, and others. Scattered across Tyrrell their technology ranges from Stone Age to early modern. Humans and Elderkin often try to sway Beastkin tribes and nations into supporting their respective sides. 

Merfolk: Mysterious and enigmatic, the merfolk are a race of sea dwelling humanoids with fish like tails instead of legs. The merfolk are divided into three subspecies who live in coral reefs, seagrass beds, and the abyssal deep respectively. While typically primitive and tribal, a few small merfolk nations have risen in the tropical seas centered around oceanic trade.    

Linpith: The Linpith are four-legged, two-armed humanoid insects from East Parthus. They are known for their diligent work efforts and hierarchical social structures, being led by queens. Originally created for conquest by the Forgotten, the Linpith began acting on their own accord once the gates were sealed. After nearly being destroyed by the Dwarves, they seek to replicate Humanity’s rapid industrialization. 

The Forgotten, also called the 'Accain' or the 'Adversary', are a race of ancient eldritch beings that walked Tyrrell's surface thousands of years ago. Much of their history has been lost over the ages or conflated with various myths and legends. All, however, are in agreement on one thing. They were supremely powerful beings who ruled the entire world with an iron fist during Tyrrell’s prehistoric era. 

However, during the first year of the First Age, the Forgotten were banished from the face of the world in an event known as the Blessed Nightmare. The Forgotten became sealed behind the Gates, 10 magical portals that lead to an accursed realm beyond Tyrrell. The Gates are located where the Leylines cross in the greatest number. 

Throughout the Second Age the Forgotten used corrupted individuals within Tyrrell, such as the "Dark Lords", to open the Gates and escape. During the Nine Gate Wars the Forgotten and their followers attempted to retake Tyrrell by force. Millions would die in these conflicts before the Forgotten suffered their last defeat in the Ninth Gate War.

The Elderkin always seek to thwart the opening of the Gates and the influence of the Forgotten. The Forgotten are, in turn pleased at Humanity’s conflicts against the Elderkin. They approve of pollution and war as it weakens the Field and the magic keeping them sealed. 

In the Third Age the Forgotten plot in secret to exploit Humanity’s new global order and exact revenge upon an unsuspecting world.