Crimson Blade Interactive — Building a Mistborn Action RPG with Physics-Accurate Allomancy

[HoleInWater]

Hey Sharders,
                                                                                                                                                                                
  We're a small indie team called Crimson Blade Interactive, and we're building a Mistborn action RPG in Unity. We've been referencing the incredible physics discussions on this forum (especially Phantine's Steel/Iron analysis) extensively, and figured this is the community to share with.                                                          
 The Game:                                                                                                                                                                     
  Open-world action RPG set in Luthadel during the Final Empire era. You play as a Mistborn with all 16 metals fully implemented.                    Our Allomancy Physics (where we leaned heavily on this community's work):                                                                                                     
  We spent a lot of time on the 17th Shard archives getting the math right:                                                                                                     
  - Linear distance scaling — F = F_max × (1 − r/R), based on the community consensus here that inverse-square doesn't work for Vin's hover equilibrium. Linear gives a clean   
  mid-range balance point where push force equals weight.   
  - Force from the chest ("center of self"), not center of mass. Blue lines originate from the chest

  - Full Newton's Third Law — mass ratios determine who moves. Push a coin and you barely move, it flies. Push a steel beam anchored to the ground and YOU launch.

Push         
  something your weight and you both move equally.                                                                                                                              
  - Anchor quality scales with mass — effectiveRange = maxRange × (1 + log10(mass) × 0.5). A coin's line is faint at 10m. A steel beam is bright at 60m.                        
  - Power-limited coin velocity — F(v) = min(F_max, P/v). This prevents hypersonic coins while explaining why fast bullets are hard to deflect (less force available at high velocity). Credits to the discussions here about why constant-force models break.                                                                                             
  - MAG burn rates — Steel/Iron 20 min, Pewter 5 min, Tin 1 hr, Atium 30 sec, etc. All from the Mistborn Adventure Game.                                                        
  - Arc trajectories — pushes at angles create smooth parabolic arcs. Force direction updates every frame as relative positions change. Diagonal steeljumps curve naturally under gravity.                                                                                                                                                                
  - Center of mass targeting — push/pull targets the mathematical center of mass, even if it's in empty space (hollow rings, bent bars). Off-center pushes create torque.       
  - Official coin specs — Clip: 2cm copper, 3g. Boxing: 3cm brass, 15.5g. From the Shire Post Mint licensed coins.                                             Vin's hover calibration (the math that validated our model):                                                                                                                  
                                                                                                                                                                                
  F_max × (1 − r_hover/R) = m × g                                                                                                                                               

  At hover: F_max ≈ 1.5 kN (conservative, enough to launch at 1g), Vin at 40kg, hover at ~55 units out of 60 range. She hovers near max range with linear falloff — exactly what the books describe. Inverse-square would give infinite force at point blank and no stable hover.
 Beyond Steel/Iron:                                                                                                                                                            
  Pewter enhancement, Tin sensory boost with vignette effects, Bendalloy/Cadmium time bubbles, emotional Allomancy (Zinc riots, Brass soothes), full enhancement metals         
  (Duralumin full-reserve burst, Chromium contact leeching, Nicrosil target boosting), Atium future shadows, Gold/Electrum self-sight, Copper clouds, Bronze seeking.
  The World:                                                

  Procedural Luthadel with Kredik Shaw (20+ spires), noble keeps, skaa quarters, canals with bridges, day/night cycle with ash-filtered sun based on latitude/declination       
  astronomy, and Preservation's mists rolling in every night with a subtle blue tint.                                                                                                   Website: https://mistborn-game.netlify.app                

  We have enormous respect for Brandon's work and this community's analysis of it. Lore accuracy is the foundation of everything we're building. If we got any of the physics wrong, you all are the people who would know — we welcome corrections.
                                                                                                                                                                                
  Looking forward to your thoughts.                         

  — Crimson Blade Interactive
 

[Denissimo He/him]

On 4/3/2026 at 11:33 AM, HoleInWater said:

Hey Sharders,
                                                                                                                                                                                
  We're a small indie team called Crimson Blade Interactive, and we're building a Mistborn action RPG in Unity. We've been referencing the incredible physics discussions on this forum (especially Phantine's Steel/Iron analysis) extensively, and figured this is the community to share with.                                                          
 The Game:                                                                                                                                                                     
  Open-world action RPG set in Luthadel during the Final Empire era. You play as a Mistborn with all 16 metals fully implemented.                    Our Allomancy Physics (where we leaned heavily on this community's work):                                                                                                     
  We spent a lot of time on the 17th Shard archives getting the math right:                                                                                                     
  - Linear distance scaling — F = F_max × (1 − r/R), based on the community consensus here that inverse-square doesn't work for Vin's hover equilibrium. Linear gives a clean   
  mid-range balance point where push force equals weight.   
  - Force from the chest ("center of self"), not center of mass. Blue lines originate from the chest

  - Full Newton's Third Law — mass ratios determine who moves. Push a coin and you barely move, it flies. Push a steel beam anchored to the ground and YOU launch.

Push         
  something your weight and you both move equally.                                                                                                                              
  - Anchor quality scales with mass — effectiveRange = maxRange × (1 + log10(mass) × 0.5). A coin's line is faint at 10m. A steel beam is bright at 60m.                        
  - Power-limited coin velocity — F(v) = min(F_max, P/v). This prevents hypersonic coins while explaining why fast bullets are hard to deflect (less force available at high velocity). Credits to the discussions here about why constant-force models break.                                                                                             
  - MAG burn rates — Steel/Iron 20 min, Pewter 5 min, Tin 1 hr, Atium 30 sec, etc. All from the Mistborn Adventure Game.                                                        
  - Arc trajectories — pushes at angles create smooth parabolic arcs. Force direction updates every frame as relative positions change. Diagonal steeljumps curve naturally under gravity.                                                                                                                                                                
  - Center of mass targeting — push/pull targets the mathematical center of mass, even if it's in empty space (hollow rings, bent bars). Off-center pushes create torque.       
  - Official coin specs — Clip: 2cm copper, 3g. Boxing: 3cm brass, 15.5g. From the Shire Post Mint licensed coins.                                             Vin's hover calibration (the math that validated our model):                                                                                                                  
                                                                                                                                                                                
  F_max × (1 − r_hover/R) = m × g                                                                                                                                               

  At hover: F_max ≈ 1.5 kN (conservative, enough to launch at 1g), Vin at 40kg, hover at ~55 units out of 60 range. She hovers near max range with linear falloff — exactly what the books describe. Inverse-square would give infinite force at point blank and no stable hover.
 Beyond Steel/Iron:                                                                                                                                                            
  Pewter enhancement, Tin sensory boost with vignette effects, Bendalloy/Cadmium time bubbles, emotional Allomancy (Zinc riots, Brass soothes), full enhancement metals         
  (Duralumin full-reserve burst, Chromium contact leeching, Nicrosil target boosting), Atium future shadows, Gold/Electrum self-sight, Copper clouds, Bronze seeking.
  The World:                                                

  Procedural Luthadel with Kredik Shaw (20+ spires), noble keeps, skaa quarters, canals with bridges, day/night cycle with ash-filtered sun based on latitude/declination       
  astronomy, and Preservation's mists rolling in every night with a subtle blue tint.                                                                                                   Website: https://mistborn-game.netlify.app                

  We have enormous respect for Brandon's work and this community's analysis of it. Lore accuracy is the foundation of everything we're building. If we got any of the physics wrong, you all are the people who would know — we welcome corrections.
                                                                                                                                                                                
  Looking forward to your thoughts.                         

  — Crimson Blade Interactive
 

You are all glorious, glorious individuals. Commendable, incredibly commendable. My respect for thee knows I no bounds. Keep working on it, please.
Sign me up for demos.

[Grubfriend He/Him]

On 4/2/2026 at 11:33 PM, HoleInWater said:

Hey Sharders,
                                                                                                                                                                                
  We're a small indie team called Crimson Blade Interactive, and we're building a Mistborn action RPG in Unity. We've been referencing the incredible physics discussions on this forum (especially Phantine's Steel/Iron analysis) extensively, and figured this is the community to share with.                                                          
 The Game:                                                                                                                                                                     
  Open-world action RPG set in Luthadel during the Final Empire era. You play as a Mistborn with all 16 metals fully implemented.                    Our Allomancy Physics (where we leaned heavily on this community's work):                                                                                                     
  We spent a lot of time on the 17th Shard archives getting the math right:                                                                                                     
  - Linear distance scaling — F = F_max × (1 − r/R), based on the community consensus here that inverse-square doesn't work for Vin's hover equilibrium. Linear gives a clean   
  mid-range balance point where push force equals weight.   
  - Force from the chest ("center of self"), not center of mass. Blue lines originate from the chest

  - Full Newton's Third Law — mass ratios determine who moves. Push a coin and you barely move, it flies. Push a steel beam anchored to the ground and YOU launch.

Push         
  something your weight and you both move equally.                                                                                                                              
  - Anchor quality scales with mass — effectiveRange = maxRange × (1 + log10(mass) × 0.5). A coin's line is faint at 10m. A steel beam is bright at 60m.                        
  - Power-limited coin velocity — F(v) = min(F_max, P/v). This prevents hypersonic coins while explaining why fast bullets are hard to deflect (less force available at high velocity). Credits to the discussions here about why constant-force models break.                                                                                             
  - MAG burn rates — Steel/Iron 20 min, Pewter 5 min, Tin 1 hr, Atium 30 sec, etc. All from the Mistborn Adventure Game.                                                        
  - Arc trajectories — pushes at angles create smooth parabolic arcs. Force direction updates every frame as relative positions change. Diagonal steeljumps curve naturally under gravity.                                                                                                                                                                
  - Center of mass targeting — push/pull targets the mathematical center of mass, even if it's in empty space (hollow rings, bent bars). Off-center pushes create torque.       
  - Official coin specs — Clip: 2cm copper, 3g. Boxing: 3cm brass, 15.5g. From the Shire Post Mint licensed coins.                                             Vin's hover calibration (the math that validated our model):                                                                                                                  
                                                                                                                                                                                
  F_max × (1 − r_hover/R) = m × g                                                                                                                                               

  At hover: F_max ≈ 1.5 kN (conservative, enough to launch at 1g), Vin at 40kg, hover at ~55 units out of 60 range. She hovers near max range with linear falloff — exactly what the books describe. Inverse-square would give infinite force at point blank and no stable hover.
 Beyond Steel/Iron:                                                                                                                                                            
  Pewter enhancement, Tin sensory boost with vignette effects, Bendalloy/Cadmium time bubbles, emotional Allomancy (Zinc riots, Brass soothes), full enhancement metals         
  (Duralumin full-reserve burst, Chromium contact leeching, Nicrosil target boosting), Atium future shadows, Gold/Electrum self-sight, Copper clouds, Bronze seeking.
  The World:                                                

  Procedural Luthadel with Kredik Shaw (20+ spires), noble keeps, skaa quarters, canals with bridges, day/night cycle with ash-filtered sun based on latitude/declination       
  astronomy, and Preservation's mists rolling in every night with a subtle blue tint.                                                                                                   Website: https://mistborn-game.netlify.app                

  We have enormous respect for Brandon's work and this community's analysis of it. Lore accuracy is the foundation of everything we're building. If we got any of the physics wrong, you all are the people who would know — we welcome corrections.
                                                                                                                                                                                
  Looking forward to your thoughts.                         

  — Crimson Blade Interactive
 

This is so incredibly cool!

Would you be willing to answer questions related to mechanics? For example, how would you mimic atium enhancing mental speed?

[Deception He/Him]

I want to test this game when you release it. I am a programmer myself, so I will be more helpful as a play tester than your average, random joe. I unfortunately cannot help actually develop the game as a part of the team, though )-:

Email [email protected] and I will tell you my real Email address that I can test from.

PLZ LET ME TEST IT SOUNDS SOOOO FUN!!!

 

Also, you probably already thought of these, but a few tips anyway:

1): Tin gives important enemies and objects glowing outlines. You can also control your camera zoom to some extent while using Tin, to zoom in on a specific object

2): You could mimic atium enhancing mental speed in a few ways: 

    - if the game is single player: slow down time within the game to give the player more time to think.

    - if the game is multiplayer: this is a bit cheap sounding, but it is your best option. Make the player automatically dodge incoming         attacks with a certain limit of dodges per minute, and give them slight aimbot.

3): You will not be able to maintain realistic physics forever. Add a system that detects when the player is attempting certain maneuvers, like if they are trying to perform a Pull slingshot, single anchor hovering, or steel jumping, then override physics for the specific action. If possible, you could add a toggle in the settings for this feature, but have it default to ON.

4): The blue line idea is great, but also not fully realistic for actual gameplay. You will need a glowy blue overlay or tint on metal objects for playability. Keep the lines, but add this tint instead.

 

You all probably already knew a lot of this, but I just wanted to say it anyway in case any of these tips are helpful to you.