Manual World Builder

The Manual World Builder gives you complete control over every element of your world. While the AI World Builder is faster, the manual path lets you precisely specify lore, mechanics, character personalities, and the exact attacks your characters can use.

World creator interface showing faction and character settings

Overview of a world’s structure

Before building, it helps to understand how Isekaigen worlds are structured. The hierarchy is:

World
└── Power System(s)
    └── Attacks / Abilities
        └── Factions  ← each faction links to a power system
            └── Classes  ← optional; each class gets a subset of attacks
                └── Characters  ← assigned to a faction and optionally a class

A character’s available abilities depend entirely on their class and faction, which depend on the power system.

Step 1 — World basics

Name

Up to 30 characters. Keep it evocative and concise.

Description

Up to 400 characters. This is the public-facing blurb shown in the world browser. Write it as a hook.

Genre

Choose from 16 genres: Fantasy, Sci-Fi, Modern, Post-Apocalyptic, Dungeon, Xianxia, Wuxia, Cyberpunk, Steampunk, Superhero, Victorian Era, Prehistoric, Space Opera, Urban Fantasy, Parallel Universe, Alternate History.

Initial History

The most important field — up to 600 characters of world lore. This text is included in every AI system message for every game played in your world. Write it like a condensed encyclopedia entry:

What happened in the world’s past
The current state of the world
Who holds power and why
The central conflict driving events

💡 Tip: The Initial History is the AI’s primary reference for your world. Make every character count — give the AI specific, usable facts rather than generic descriptions.

Step 2 — Power Systems

A power system defines the framework of abilities in your world. Every attack belongs to a power system.

Name — Up to 50 characters (e.g., “Spirit Blade Arts”, “Demon Channeling”)
Description — Up to 400 characters explaining how the power system works

You can create 1 or 2 power systems per world. Most worlds have one. Multiple power systems allow fundamentally different ability types for different factions.

Step 3 — Attacks

Attacks are the individual abilities characters can use. Every attack belongs to a power system.

Field	Options
Name	Up to 100 characters
Type	Melee or Projectile
Effect	None, Burn, Freeze, Poison, Shock, Bleed, or Stun
Damage	Numerical value
Stamina Cost	Stamina required to use
Level	Minimum level required
AoE	Area of effect (1 = single target)
Description	Narrative description of the attack

📝 Note: The Level field restricts which characters can use an attack based on their current game level. Plan your attack roster with progression in mind.

Step 4 — Factions

Factions are the political, cultural, or organizational groups that divide your world. Every character belongs to a faction.

Name — Up to 50 characters
Description — Up to 400 characters
Power System — Which power system this faction uses
Image — Optional faction banner or logo

How attacks work with factions

If a faction has no classes, every character in that faction can use all attacks from the faction’s power system.

If a faction has at least one class, characters must belong to a class and can only use the attacks assigned to their class.

Step 5 — Classes (Optional)

Classes are optional sub-groups within a faction that give different characters within the same faction different ability loadouts.

For example, a warrior faction might have:

Sentinel class — heavy melee attacks, high AoE
Blade Dancer class — fast single-target attacks
Battle Priest class — support abilities plus one offensive attack

Class rules

A class’s attacks must be a subset of its faction’s power system attacks — you cannot assign attacks from a different power system
Once a class exists in a faction, all characters in that faction should be assigned to a class

Class fields

Name — Up to 100 characters
Description — Narrative description of the class
Faction — Which faction this class belongs to
Attacks — Multi-select from the faction’s power system attacks
Image — Optional class image

Step 6 — Characters

Characters are the playable protagonists your world offers. At least one is required (the default main character).

Field	Details
Name	Up to 50 characters
Gender	Male, Female, Other
Background	Up to 600 characters — history, origin, motivations
Personality	Up to 600 characters — how the character thinks and speaks
Faction	Which faction they belong to
Class	Which class (optional if faction has no classes)
Image	Portrait image
Starting Text	The opening scene shown when someone starts a game with this character

Personality traits (slider mode)

Instead of writing personality as text, you can set 7 numerical trait values:

Wisdom, Generosity, Integrity, Empathy, Courage, Temperance, Influence

These feed directly into the Personality Compatibility system. Text mode and slider mode can be used together — they complement each other.

Quirks

Add short descriptive tags that further define a character for the AI. Examples: “Speaks in riddles”, “Never shows fear”, “Secretly kind despite a rough exterior.”

Step 7 — Set the default character

Designate one character as the default main character in world settings. This is what players see first when they open your world’s page. Make it your most compelling protagonist.

Publishing

Toggle Public in world settings when your world is ready. Your world will appear in the Isekaigen world browser. You can make it private again at any time.

Tips for a great world

Write the Initial History last. Once you know all your factions and characters, you’ll write better lore.
Keep attack names thematic. “Shadow Step Slash” is more immersive than “Attack 3” — the AI uses attack names in combat narration.
Give each character a distinct starting text. The opening scene is the first thing a player reads — make it grab them.
Use personality sliders alongside text. Sliders handle the mechanical compatibility system; text handles nuance the sliders can’t capture.
Test before publishing. Start a game in your own world in both Story and RPG modes. Adjust the Initial History based on how the AI responds.