Why Yuumi is So Overpowered in League of Legends

League of Legends is independent from the extended lore of Runeterra, and is published through comics, short stories, and animated shorts.

League is the primary driver of the intellectual property's expanded universe via champion releases and gameplay updates, which are accompanied with updated lore. Given the nature of its development, Runeterra is made up of an assortment of genre staples, with regions and factions all possessing recognisable characteristics from wider popular culture. Cass Marshall of Polygon writes the lore is "a collection of genres ranging from Lovecraftian horror to knights and banners fantasy to pirate power struggles."

Demacia is a powerful region with a medieval European aesthetic that values chivalry and is known to oppress magic-users. Noxus is an empire that is reminiscent of the Roman Empire, and is ruled by a triumvirate. It is known for its aggressive military aggression, expansionism, and high valuation of might. Piltover and Zaun are twin cities inspired by steampunk writing: Piltover, the city of progress, exploits the under-city of Zaun to maintain its rapid technological advancement, while Zaun is depicted as dirty and its champions are often criminals or orphans. The Freljord is an ice-covered land in the north of Runeterra, where ancient, trapped horrors sleep beneath the ice while rival kingdoms fight in a civil war. Bandle City is the home of yordles, child-sized fae beings, and exists in the Spirit Realm, generally inaccessible to mortals. Yordles exist in most regions of Runeterra and take on the traits of the region they belong to.

Ionia is not a formal nation, but a large archipelago inspired by Eastern mysticism, with monks and ninjas who wield spirit and shadow magic. It is the primary residence of many Vastaya, animal-human hybrids with a strong connection to Ionia's natural magic. To the south of Ionia is Bilgewater, a port city in the Serpent Isles filled with pirates, bounty hunters, gamblers, and a sea monster fishing industry. Southeast of Bilgewater are the Shadow Isles, another archipelago which was corrupted by an ancient ritual gone wrong. A malign force known as the Black List permeates the isles and empowers undead beings.

Shurima is the largest continent of Runeterra. It is a vast desert and is largely occupied by nomadic tribes; there was once an ancient empire that was based on Ancient Egyptian mythology. Targon is a region that is reminiscent of Greek mythology, and includes Mount Targon, the tallest peak in Runeterra, and a gateway to a realm occupied by celestial beings. The Void, deeply inspired by Lovecraftian horror and the Cthulhu mythos, is a separate dimension populated by cosmic horrors that enter Runeterra through portals.