Ultimate Shin Megami Tensei 3 Fusion Calculator | SMT Nocturne Guide


Shin Megami Tensei 3 Fusion Calculator

Your essential tool for mastering demon fusion in SMT: Nocturne HD Remaster.



Select the first demon for fusion.


Select the second demon for fusion.

Fusion Level Comparison

A visual comparison of the base levels of the ingredient demons and the fusion result.

What is the Shin Megami Tensei 3 Fusion Calculator?

The shin megami tensei 3 fusion calculator is a powerful tool designed to help players navigate the complex demon fusion system in Shin Megami Tensei III: Nocturne. Fusion is the primary method for acquiring new, more powerful demons by combining two or more existing demons in your party. This calculator simplifies the process, allowing you to predict the outcome of a fusion before committing to it in-game, saving you time and Macca. Understanding these mechanics is crucial for success, and a reliable fusion calculator is an indispensable part of any player’s strategy.

The SMT3 Fusion Formula and Explanation

Demon fusion in SMT3 follows a specific set of rules. The primary outcome is determined by the races of the two demons being fused. A fusion chart dictates the resulting demon’s race. Once the race is determined, the game uses a formula to find the specific demon within that race.

The core formula is:

Resulting Level = floor((Demon 1 Base Level + Demon 2 Base Level) / 2) + 1

The game then finds the demon of the target race with the lowest base level that is equal to or higher than this ‘Resulting Level’. This means you won’t always get a demon with the exact calculated level. If you’re interested in game mechanics, you might also enjoy reading about advanced gaming strategies.

Fusion Variables

Key variables that influence the outcome of a shin megami tensei 3 fusion calculator.
Variable Meaning Unit / Type Typical Range
Demon 1 Race The family or tribe of the first demon. Race Name (e.g., Fairy, Beast) N/A
Demon 2 Race The family or tribe of the second demon. Race Name (e.g., Yoma, Night) N/A
Demon Base Level The demon’s starting level, not its current level. Level (Integer) 1 – 95
Resulting Race The race of the demon produced, based on a fixed chart. Race Name N/A

Practical Examples

Example 1: Fusing a Mid-Level Demon

  • Inputs:
    • Demon 1: Beast Inugami (Base Level 17)
    • Demon 2: Yoma Apsaras (Base Level 10)
  • Calculation:
    • Resulting Race (Beast + Yoma): Avian
    • Average Level: floor((17 + 10) / 2) + 1 = 13 + 1 = 14
  • Result: The calculator searches the Avian race for the first demon at or above level 14. This results in Avian Phoenix (Base Level 18).

Example 2: A Higher-Level Fusion

  • Inputs:
    • Demon 1: Divine Principality (Base Level 29)
    • Demon 2: Snake Naga (Base Level 23)
  • Calculation:
    • Resulting Race (Divine + Snake): Vile
    • Average Level: floor((29 + 23) / 2) + 1 = 26 + 1 = 27
  • Result: The calculator searches the Vile race for the first demon at or above level 27. This results in Vile Pazuzu (Base Level 33). For more tips on optimizing your team, see our guide on team-building in RPGs.

How to Use This Shin Megami Tensei 3 Fusion Calculator

Using this calculator is a straightforward process designed to give you quick and accurate results.

  1. Select First Demon: Use the first dropdown menu to choose the first demon you want to fuse. The list is populated with demons from SMT3.
  2. Select Second Demon: Use the second dropdown menu to select the other demon for the fusion.
  3. Click ‘Fuse Demons’: Press the “Fuse Demons” button to perform the calculation.
  4. Review Results: The tool will display the name of the resulting demon, its race, and its base level. It also shows the intermediate calculation for transparency.
  5. Analyze Chart: The bar chart below the calculator visually compares the base levels of the ingredient demons and the final result, helping you quickly see the level jump.

Key Factors That Affect Shin Megami Tensei 3 Fusion

While our shin megami tensei 3 fusion calculator covers standard fusions, several other factors can influence the outcome in-game.

  • Demon Race: This is the most critical factor. The combination of two races determines the resulting race according to a fixed fusion chart guide.
  • Base Level: Only the base level matters for the calculation, not the demon’s current level from experience gain.
  • Kagutsuchi Phase: The phase of the moon-like Kagutsuchi can affect fusion. For instance, sacrificial fusions can only be done during a Full Kagutsuchi.
  • Sacrificial Fusion: At Full Kagutsuchi, you can sacrifice a third demon to provide a massive EXP boost to the newly fused demon. This doesn’t change the result, but it powers up the new demon significantly.
  • Fiend Fusions: Fusing specific combinations during a Full Kagutsuchi while holding a Deathstone can result in a powerful, secret Fiend demon. This is a topic that many game lore discussions cover in detail.
  • Cursed State: If the Demi-fiend protagonist is in a “Cursed” state (from equipping certain Magatama), the entire fusion chart changes, leading to different, often darker, results.
  • Special Fusions: Some demons, often powerful and high-level ones, require very specific combinations of two or even three demons and cannot be created through normal fusion.
  • Evolutions: Some demons will evolve into a stronger form upon reaching a certain level. These evolutions cannot be created via fusion directly.

Frequently Asked Questions (FAQ)

Why did I get a different demon than the shin megami tensei 3 fusion calculator showed?

This can happen due to a few in-game factors not accounted for in this standard calculator, such as being in a “Cursed” state, or attempting a fusion during a specific Kagutsuchi phase that might trigger a Fiend fusion.

Can I fuse a demon that is a higher level than my character?

No, you cannot create a demon via fusion that has a higher base level than the Demi-fiend’s current level. The option will be grayed out in-game.

What is a fusion accident?

A fusion accident is a random event where the fusion fails and produces an unexpected demon, which can be either weaker or sometimes stronger than the intended result. The chance of an accident is very low but increases during a Full Kagutsuchi.

Does the order of demons in the calculator matter?

For this standard two-demon fusion calculator, the order does not matter. Fusing Demon A with Demon B gives the same result as fusing Demon B with Demon A.

How are skills inherited in a fusion?

Skill inheritance is a complex system. The resulting demon can inherit a certain number of skills from its parents. In the HD Remaster, you can now choose which skills to inherit, a massive quality-of-life improvement over the original’s random inheritance.

What about Elemental and Mitama fusions?

Fusing with Elementals (Erthys, Aeros, etc.) will rank a demon up or down within its own race. Fusing with Mitama (Saki, Kusi, etc.) does not change the demon but provides stat boosts and lets you add the Mitama’s skills.

Why can’t I fuse two demons of the same race?

Fusing two demons of the same race usually results in an Elemental, not another demon of that race. This is a core mechanic of the fusion system.

Is this tool updated for the SMT3 HD Remaster?

Yes, the fusion logic in the HD Remaster is identical to the original Nocturne Maniax version, so this calculator is fully compatible and accurate.

Related Tools and Internal Resources

If you found this shin megami tensei 3 fusion calculator helpful, you might be interested in our other resources for dedicated gamers:

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