Maxwell's Thermic Engine - New greatsword weapon (DLC)
🟠 Updated over a year ago⚠️ Install Order · 2 steps
Install in this order, then this mod last — most mods fail to load without their framework and dependencies in place.
Preview

🔍 Analysis
- 👍 3.7% endorsement rate — high engagement, a strong quality signal
- 🏆 #278 of 344 Weapons mods in this game by downloads
📋 About This Mod
Updated to work with the DLC - last working on regulation version 1. 16. Available on Ab Aeterno's Moveset Modpack (v1. 4. 2+).
I'll be surprised if anyone gets what this one references.
Adds a new weapon, "Maxwell's Thermic Engine", which has innate fire and magic damage. Landing attacks with it grants you a stacking buff that further increases fire and magic damage. Land enough attacks and the sword will fully charge, granting a multiplicative boost to fire/magic damage, and allowing you to use a special version of the ash of war. Internal weapon ID is 3042000.
You can purchase it at the Twin Maiden Husks (under the "Special Weaponry Shop" option) for 3500 runes (knight's greatsword icon).
Ash of War: Thermal Dissipation
Similar to Square Off but has different, 2-part R1 and R2 follow-ups.
When the weapon is fully charged, these follow-ups become greatly enhanced, but consume the sword's buffs upon use. The R1 is ice-themed (causes frost buildup), and the R2 is fire-themed.
Showcase video:
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Installation:
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[]You'll need ModEngine2, you can find releases & installation instructions here: https://github.com/soulsmods/ModEngine2
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]Download the mod. You can then extract the 'maxwell_thermic_engine' folder's contents into ModEngine2's 'mod' folder, or add the 'maxwell_thermic_engine' folder itself and link to it in ModEngine2's "config_eldenring.toml" file.For modding:
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[]TAEs: added a238.tae and a627.tae
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]HKX: a238 and a627 files found in c0000_a6x.anibnd.dcx[]HKS: uses ivi's c0000.hks script, adding the "HasMaxwellEngine", "MaxwellEngineFP" and "MaxwellEngineAoWProc" functions. You can search for "maxwell" to go through the comments above the changes made.
There's a commented bit near the top, "event debug log", which I forgot to delete but you can ignore (I used it to write a file log to see the character's animation names).[]Parts: adds a new weapon model 8013
[]Events: adds events 708 and 709, initialized and defined in the common.emevd.dcx
[]Edited CSVs: AtkParam_Pc, AttackElementCorrectParam, BehaviorParam_PC, Bullet, EquipParamWeapon, ShopLineupParam, SpEffectParam, SpEffectVfxParam, SwordArtsParam
I have a ko-fi if you feel like supporting me: https://ko-fi.com/abaeterno42
Special thanks to Blubber for the Sekiro animations! (From here, used in the ash of war's R1 follow-up)
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[]TAEs: added a238.tae and a627.tae
Adds Maxwell's Thermic Engine, a new greatsword inspired by DCSS, featuring a ramping fire/magic damage mechanic and a related Ash of War. A niche weapon mod for Elden Ring players seeking a unique, thematic addition, with modest community traction (49 endorsements).
✨ Key Features
📊 Pros & Cons
✅ Pros
- Unique homage to DCSS fans—brings a beloved weapon concept into Elden Ring.
- Ramping damage mechanic adds a fresh twist to combat, rewarding sustained aggression.
- Comes with its own Ash of War, so you get a complete package without hunting for extras.
⚠️ Cons
- Small mod with only 49 endorsements—might have untested balance or bugs.
- Requires the DLC to use, which locks out base-game-only players.
For Elden Ring players who love DCSS and want a thematic, mechanically interesting greatsword. Also for collectors of unique weapons who enjoy experimenting with new damage mechanics. Skip if you're looking for a fully documented, polished weapon overhaul—this is a niche addition.
💡 Beginner Tips
- Make sure you own the Shadow of the Erdtree DLC—this mod requires it to work.
- Test the ramping mechanic on low-level enemies first to get a feel for the damage curve.
- If you're using a mod manager, let it handle the file placement to avoid overwriting game files.
📊 Mod Details
- Game
- Elden Ring Mods
- Author
- Ab Aeterno
- Version
- 1.1
- Downloads
- 1,312
- Endorsements
- 49
- Category
- Weapons
- Created
- 11/1/2023
- Updated
- 11/18/2024
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