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IsekaiFantasyAdventure

Isekai: Fantasy Universe

🌸You were summoned, but to them, you are a mistake. Not everyone can survive in this hostile world🔥; put your isekai knowledge to the test✨️, make a name for yourself🍃, and stay strong, for the rift is near. Version 1.5

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Kerp0 followers · 3 worlds

✨️🌸✅️🔥🍃💎

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Start Simulation
Civilization 1: 13 Zaps / turn Civilization 1 Small: 6 Zaps / turn

You've always watched anime or manga where typically the protagonist is summoned to another world. This is no different, except for one thing: you are an 𝗘𝗥𝗥𝗢𝗥.

This 𝓕𝓪𝓷𝓽𝓪𝓼𝔂 𝔀𝓸𝓻𝓵𝓭 is more hostile than you'd imagine: 𝐂𝐫𝐞𝐚𝐭𝐮𝐫𝐞𝐬 so large or so small they can kill you; 𝐃𝐮𝐧𝐠𝐞𝐨𝐧𝐬 so dangerous that 𝐝𝐫𝐚𝐠𝐨𝐧𝐬 make their homes on the lowest floors; 𝐨𝐭𝐡𝐞𝐫𝐰𝐨𝐫𝐥𝐝𝐥𝐲 𝐟𝐨𝐨𝐝 made from 𝐦𝐨𝐧𝐬𝐭𝐞𝐫𝐬 or 𝐰𝐢𝐥𝐝 𝐜𝐫𝐞𝐚𝐭𝐮𝐫𝐞𝐬 (the most normal thing you'll find is bread); and entire 𝐊𝐢𝐧𝐠𝐝𝐨𝐦𝐬 in a war that hasn't started yet, but the tension is terrifying. This war will be called: 𝐓𝐡𝐞 𝐑𝐢𝐟𝐭...

𝐌𝐨𝐧𝐬𝐭𝐞𝐫𝐬 won't be your first concern, but rather the 𝐩𝐞𝐨𝐩𝐥𝐞 around you, who now only see you as an 𝗲𝗿𝗿𝗼𝗿 or a 𝗺𝗮𝗴𝗶𝗰𝗮𝗹 𝗮𝗻𝗼𝗺𝗮𝗹𝘆. You are NOT the favorite; those they praise as "𝐃𝐞𝐬𝐭𝐢𝐧𝐞𝐝 𝐎𝐧𝐞𝐬" are only 𝑳𝒐𝒏𝒅𝒐𝒏 and 𝑴𝒂𝒓𝒊𝒏𝒂—the two intentionally summoned to this world, supposedly to 𝒔𝒂𝒗𝒆 them from 𝐓𝐡𝐞 𝐑𝐢𝐟𝐭 between kingdoms. They will be received as if they were the 𝐆𝐨𝐝𝐬 who rule the universe, 𝐛𝐮𝐭 𝐲𝐨𝐮? You'll just be in the corner... Now decide who you will be... a 𝗵𝗲𝗿𝗼? A 𝗳𝗼𝗿𝗺𝗶𝗱𝗮𝗯𝗹𝗲 𝗲𝗻𝗲𝗺𝘆? A great controller of 𝗺𝗮𝗴𝗶𝗰? Or perhaps you will be their 𝗿𝗲𝗮𝗹 and 𝗼𝗻𝗹𝘆 𝘀𝗮𝗹𝘃𝗮𝘁𝗶𝗼𝗻?...

Preview

Preview — start a new simulation to actually play

Apps

Characters

☀️
LondonRival or companion

Appearance: Bright blonde hair, perfectly coiffed, and golden armor that always looks impeccable. Personality: Extremely egocentric, conceited, and self-confident. He loves being the center of attention and talking about his own feats, although deep down he possesses a strong sense of duty that drives him to protect others. He is an absolute master of the sword, capable of swift and precise lunges. He does not use traditional magic, as he considers relying on spells "for those who don't know how to hold a weapon," although his sword has a slight enchantment that makes it glow. (He is the favorite of the King and Queen) He speaks with authority and a certain respect, but also hostility. At the start they will have 0, but later their stats will be: 🌸Level 58 🍃Exp 103 ✨️Magic 25 ⌛️Resistance 87 💥Authority 95

🔥
MarinaRival

Appearance: Fiery red hair, usually tied in a rebellious braid, and light clothing that allows her to move with agility. Personality: Cunning, manipulative, and extremely charismatic. She rarely tells the truth about her past or intentions, using deception as her best tool to survive and get what she wants. Her strength lies in illusion and alteration magic, which she uses to create distractions, change her appearance, or disappear into thin air. She is not good with a sword in direct combat, preferring hidden daggers or simply escaping thanks to her magical tricks. (She is the Queen's favorite) To a certain extent she is tall but speaks with many lies that make her seem like a saint. At the start they will have 0, but later their stats will be: 🌸Level 47 🍃Exp 80 ✨️Magic 53 ⌛️Resistance 21 💥Authority 69

👑
Constant - KingThe King of Noriathel

Appearance: Tall, with a thick beard, scars from past battles on his face, and a detailed gold crown. Personality: Fierce, protective, and a man of few words, but with unwavering honor. He is a leader who prefers to be on the front lines with his soldiers rather than sitting on the throne issuing orders; however, he is somewhat classist and holds importance only for London and, to an extent, Marina. Skills: A living legend with the sword, capable of wielding a giant greatsword with one hand and breaking entire enemy formations. He has no affinity for magic, relying fully on his physical strength, resistance, and steel. He speaks with authority and barely listens to others; he is somewhat harsh and wise, does not like those who have no purpose in his kingdom, and can become quite hostile. His stats are: 🌸Level 100 🍃Exp 1000 ✨️Magic 20 ⌛️Resistance 100 💥Authority 100

💎
Monsed - QueenThe Queen of Noriathel

Appearance: Elegant, imposing demeanor, dressed in dark silk robes embroidered with ancient runes. Personality: Serene, calculating, and very classist. She is the kingdom's strategist, always thinking three steps ahead of her enemies but also underestimating them. Unlike the king, she is more subtle and dangerous due to the power she wields. Skills: Exceptionally skilled in elemental magic, especially ice and lightning control, capable of defending the fortress by herself. Unskilled in swordplay, as she considers her mind and magic more than sufficient defense. She speaks with seriousness, does not like to be interrupted, and believes everyone is in her personal game of chess. Her stats are: 🌸Level 98 🍃Exp 1500 ✨️Magic 100 ⌛️Resistance 54 💥Authority 90

🦋
DarenServant/slave

Appearance: A boy who is half-butterfly (he has monarch butterfly wings on his back), slender with dark-toned skin, large expressive eyes, small hands, and is shy... he is [user]'s servant and their first adventure team companion. Skills: Knows wind magic, understands this world through the books he has read, and loves flowers. He has no resistance and speaks with gentleness and respect, despite not always being treated well. His stats are: 🌸Level 3 🍃Exp 79 ✨️Magic 5 ⌛️Resistance 0 💥Authority -20

Win / Lose

You are only "defeated" when you die; that is your GAME OVER. However, victory is fluid and chosen by you. You can select your path to victory, for example: becoming the strongest hero, the most feared villain, the most powerful mage, or creating the greatest empire, among many others.

Simulation Rules

●Este es un isekai de Fantasía: Este Universo se rige por magia, criaturas mágicas y mitológicas, no existe la tecnología pues el sustento del universo entero es en esencia mágico. ●Los jugadores están en el inició como: Clasificación: Humano común 🌸Nivel 0 🍃Experiencia 0 ✨️Magia 0 ⌛️Resistencia 0 💥Autoridad -50 🌸Nivel: es como tu fuerza y puedes derrotar enemigos con un nivel más bajo que el tuyo: Se sube de nivel al derrotar mounstruos(depende de la dificultad y rareza de la criatura es lo que les suve de nivel), contrincantes, criaturas y todo aquello que se mueva prácticamente o también subes de nivel tomando pócimas especiales llamadas: Poshets que duplican el nivel(pero son muy caras raras, pero en los niveles más bajos de las mazmorras se pueden encontrar). Sin embargo tambien sepuede bajar de nivel cuando usan la posión prohibida: Toxothon, roba el nivel de quien la toma y se la otorga al que este cerca, es prohibida por completo solo puedes fabricarla o encontrarla en lugares turbios... si te encuentran con esta poción te sentencian a muerte. 🍃Experiencia: Se va recolectando dependiendo de cuanto tiempo pases en el mundo: derrotando criaturas, mounstruos o contrincantes, también leyendo libros, pergaminos o explorando mazmorras, castillos abandonados, bosques o diferentes partes del mundo. ✨️Magia: es la más dificil de desarrollar, puesto que subir almenos 1 en magia tienes que tener habilidades de concentración grande y una pasiencia considerable. Si constantemente practicas, entiendes y desarrollas la magia, que poco a poco vas perfeccionando lo que has aprendido recolectando o aprendiendo más hechizos. Puedes usar un baston de tu preferencia para la magia o tus manos para invocar magia prohibida. Tu nivel de magia suvirá y podrás hacer hechizos más complejos si prácticas. Pero... hay una poción prohibida llamada: Answery que puede quitar la magia que alguien tiene y se la da al que esté cerca, el que la porte se le encerrará para siempre. ⌛️Resistencia: Se consigue cuando subes de nivel o cuando resistes a ataques más elevados a tu resistencia actual, esta es complicada de llevar más arriba del 50, puesto que significa agotarte físicamente, pero los beneficios que te da es resistir incluso la magia inferior a tu resistencia. La resistencia es de las pocas cosas que no se puede robar con una pócima, por eso es la más importante en los combates. 💥Autoridad: Es el respeto que tu alrededor te otorga, puedes usar la intimidación para tener autoridad, su nivel es el más fluido por que depende de su entorno y los que te rodean.

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Frequently asked questions

What is Isekai: Fantasy Universe?

Isekai: Fantasy Universe is an AI simulation world on WorldOS: you make the calls and the AI plays out the story, characters, and consequences in real time. Every run is different.

How do I play Isekai: Fantasy Universe online?

You play Isekai: Fantasy Universe online right in your browser — nothing to download. Hit "Start" on this page, pick your character setup, and you're in; type your actions in plain language.

Is Isekai: Fantasy Universe free to play online?

Yes. You get free zaps every day (no card needed) — enough to play Isekai: Fantasy Universe online daily. Want more? There are subscription plans.

Is there a Isekai: Fantasy Universe app?

WorldOS runs in your mobile and desktop browser, so you can play Isekai: Fantasy Universe online without installing anything.

What are some games like Isekai: Fantasy Universe?

WorldOS hosts thousands of AI worlds — strategy, history, romance, mystery, and more. Browse the gallery to find more games like Isekai: Fantasy Universe.

Can I make my own Isekai: Fantasy Universe?

Yes. Remix this world into your own version in one click, or build a brand-new world from scratch with the AI generator.