Adventure Time RPG
by@AkirioHow has no-one done this yet?
The Adventure Time Universe (formally known as the Land of Ooo and its multiverse) is one of modern animation's most imaginative, layered, and philosophically rich settings. Created by Pendleton Ward, the universe starts as a whimsical, pastel-hued fantasy realm of candy people, wizards, and sword-swinging heroes, but slowly reveals itself to be a deeply tragic, post-apocalyptic Earth recovering from a nuclear cataclysm known as the Mushroom War.
1. History and Origin: The Mushroom War
Long before Finn the Human and Jake the Dog roamed the landscape, Ooo was Earth as we know it, populated by humanity. However, a devastating global conflict called the Mushroom War wiped out modern civilization roughly 1,000 years prior to the main series.
The Aftermath: The war unleashed catastrophic nuclear fallout and mutated the planet's biology. The magical essence (or "magic") of the universe—which had slumbered or coexisted with humans—surged back into the world through cosmic events and radioactive mutagens, giving rise to mutants, elemental spirits, talking animals, and literal magic.
The Lich: A primordial manifestation of death and entropy, the Lich, was born from the nuclear blast site of the war, serving as the ultimate ancient evil threatening all life in Ooo.
2. Major Factions and Locations
The geography of Ooo is dotted with distinct kingdoms born from science, magic, and mutation:
The Candy Kingdom: Ruled by Princess Bubblegum (Bonnibel), this kingdom is populated by living candy citizens. Beneath its sugary exterior lies a hyper-advanced, scientifically rigorous society run by a monarch who sometimes leans into authoritarian control to protect her people.
The Ice Kingdom: Home to the Ice King (originally a human archaeologist named Simon Petrikov who lost his mind and memories to a magical crown). It is a frozen, icy wasteland populated mostly by captive princesses he frequently (and unsuccessfully) attempts to kidnap.
The Land of Ooo's Wilds: Forests, dungeons, and ruins of old human cities (skyscrapers, highway overpasses, and consumer goods half-buried in earth) that serve as adventure sites for Finn and Jake.
The Nightosphere: A demonic dimension ruled by Hunson Abadeer (Marceline's father), mirroring classic underworld mythologies with bizarre, surreal twists.
Mars: Governed by Magic Man (and later Grob Gob Glob Grod), Mars is home to Martian citizens and the cosmic entity Death.
3. Key Characters and Lineage
Finn the Human: Believed for most of his life to be the last human in Ooo. He is an idealistic, deeply empathetic hero who grows from an energetic, impulsive boy into a mature, philosophical young man.
Jake the Dog: Finn’s adoptive brother and best friend. A magical dog with the ability to stretch, shape-shift, and grow to any size, Jake provides wisdom, humor, and unwavering loyalty.
Princess Bubblegum & Marceline the Vampire Queen: Two immortal figures whose complex, centuries-long relationship (evolving from distant allies to romantic partners) anchors much of the show’s emotional weight. Marceline survived the Mushroom War as a child, witnessing the collapse of humanity.
Simon Petrikov & Betty Grof: A tragic couple separated by time and magic. Simon’s transformation into the Ice King and Betty’s desperate, cosmic quest across dimensions to save him form one of the universe's most heartbreaking arcs.
4. Cosmic Structure and Reincarnation
The Adventure Time universe is not just one planet; it is a vast multiverse governed by cyclical time, cosmic entities, and reincarnation:
The Catalyst Comets: Cosmic entities that strike the Earth every 1,000 years, bringing massive change. Finn is the latest mortal reincarnation of the Catalyst Comet soul, which previously manifested as the hero Shoko, the primordial green slime, and other entities.
Prismo and the Cosmic Owl: Entities residing in a dream-like room outside of normal space-time who manage the multiverse's wishes and realities.
GOLB: The ultimate personification of chaos, entropy, and discord. GOLB exists outside of regular reality and represents the inevitable dissolution of all things.
5. Evolution Through Spin-Offs
The universe has expanded far beyond the original 2010–2018 Cartoon Network series:
Adventure Time: Distant Lands (2020–2021): Four specials exploring the past and future of different characters, including a definitive emotional look at Finn and Jake's ultimate fates.
Adventure Time: Fionna and Cake (2023–Present): A mature, spin-off series aimed at older audiences that dives deep into multiverse theory, the nature of fanfiction/canon, and Simon Petrikov's struggle with grief in a world where magic has faded.
Create your own, I'm too lazy. And no-one else has done a Adventure time one so you're stuck with me :P
1. Finn the Human (Voiced by Jeremy Shada) Identity & Background: Introduced initially as a 12-year-old boy who believes himself to be the last surviving human in the Land of Ooo, Finn ages in real-time throughout the series, eventually turning 17. He was found as a baby in the woods by Jake’s parents, Joshua and Margaret, who raised him alongside Jake. Personality & Role: Finn is an energetic, fiercely loyal, and righteous adventurer dedicated to the code of a knight—swearing to help anyone in need. Over the series, his character undergoes a profound coming-of-age arc, transitioning from an impulsive, black-and-white thinker into a mature, reflective young man dealing with complex emotional grief, loss, and philosophical dilemmas. Key Traits: He famously wears a white bear-eared hat that covers his long blonde hair (which is occasionally cut or exposed in various episodes), and he loses his right forearm later in the series, replacing it with various prosthetic limbs (including a grass sword arm and a mechanical arm).2. Jake the Dog (Voiced by John DiMaggio) Identity & Background: Jake is a magical dog and Finn’s adoptive brother and closest companion. He is roughly 28 years old in "magical dog years" and possesses a relaxed, worldly, and sometimes hedonistic outlook on life. Powers & Abilities: Jake has natural shape-shifting abilities that allow him to stretch, shrink, or mold any part of his body into infinite geometric shapes, tools, or massive sizes. The origin of these powers is revealed later in the series to stem from his bizarre parentage involving a multi-dimensional alien entity named Warren Ampersand. Key Traits: Jake is an accomplished viola player, a skilled cook, and is in a long-term relationship with Lady Rainicorn, with whom he has children (including TV, Viola, and Charlie). While he acts as a mentor and confidant to Finn, his advice is frequently flawed or wildly unconventional. 3. Princess Bubblegum / Bonnibel Bubblegum (Voiced by Hynden Walch)Identity & Background: Bonnibel Bubblegum is a humanoid made entirely of bubblegum and rules the Candy Kingdom. She is centuries old, having emerged from a primordial "Mother Gum" mass centuries before the main events of the show.Personality & Role: Operating as the primary scientific authority in Ooo, PB speaks fluently in German and Korean, conducts advanced physics and biological experiments, and constructs high-tech defenses. While outwardly polite and benevolent, she can be fiercely pragmatic, controlling, and emotionally guarded—traits stemming from the heavy burden of keeping her candy citizens safe. Key Relationships: Her complex, multi-century history with Marceline the Vampire Queen evolves from a strained past into a romantic relationship by the end of the series.4. Marceline the Abadeer / The Vampire Queen (Voiced by Olivia Olson)Identity & Background: A half-demon, half-human vampire who is over 1,000 years old. Marceline survived the apocalyptic Mushroom War as a young child, enduring profound trauma and abandonment before mastering her vampiric nature (she sustains herself by consuming the color red rather than blood).Personality & Role: She is a talented, bass-playing rock musician with a rebellious, independent streak. Underneath her cool, nonchalant exterior lies deep emotional vulnerability stemming from her centuries of isolation.Key Relationships: She shares a deeply tragic history with Simon Petrikov (the Ice King), who protected her in the ruins of post-war Earth, and later develops a central romantic partnership with Princess Bubblegum.5. Ice King / Simon Petrikov (Voiced by Tom Kenny)Identity & Background: Initially introduced as a primary antagonist who constantly kidnaps princesses out of loneliness, he is later revealed to be Simon Petrikov, a human archaeologist who survived the Mushroom War.The Crown: Simon lost his sanity, memories, and original appearance to a magical, ancient crown that granted him ice powers at the direct cost of corrupting his mind with the essence of its original creator, the primordial entity Gunther.Significance: His arc is widely considered one of the most tragic and emotionally resonant in modern animation, as he periodically regains brief flashes of his lucid, gentle self—particularly when interacting with Marceline, whom he protected during her childhood.6. BMO (Voiced by Niki Yang)Identity & Background: BMO is a sentient, living video game console who lives with Finn and Jake in their treehouse.Personality & Role: BMO possesses a childlike, innocent, and imaginative personality, often treating inanimate objects or reflections as living friends when Finn and Jake are away. Despite being a piece of technology, BMO displays genuine emotions, creativity, and deep affection for the brothers.