Eye for an Eye
Fully updated for Factorio 2.0 and Space Age.
Overview
When an enemy damages your buildings, they get a taste of their own medicine. Eye for an Eye reflects a configurable percentage of damage back to any attacker that hits a player-owned structure. Every enemy kill also reduces the global evolution factor, giving you a tangible reward for successful defence.
"An eye for an eye makes the whole world blind" – but in Factorio, it makes the biters think twice.
Features
- ⚡ Reflection Damage – Any enemy that damages your buildings receives a configurable percentage of that damage back (default: 20%). Fully adjustable from 0% to 10,000%.
- 📉 Evolution Reduction – Every enemy kill reduces the global evolution factor by a configurable amount. Turn the tide against the biters!
- 🏗️ Nest Destruction Control – Optionally prevent spawner destruction from adding evolution (enabled by default).
- 🔧 Fully Configurable – All settings are runtime-global and take effect immediately. No restart required.
- 📝 Chat Spam Control – Disable chat messages for mass killing sessions.
- 🛠️ Debug Logging – Optional verbose logging to
factorio-current.logfor troubleshooting. - ✅ Verified for Factorio 2.0.77+ and Space Age – Tested and confirmed working.
How It Works
- Reflection: When an enemy attacks a player-owned building, the mod calculates a percentage of the damage dealt and applies it back to the attacker as electric damage.
- Evolution Reduction: Each time an enemy entity dies, the mod subtracts the configured amount from the global evolution factor.
- Nest Destruction: By default, destroying spawners adds zero evolution – you can disable this in the settings.
Settings
All settings are available in Settings → Mod Settings → Runtime Global:
| Setting | Default | Description |
|---|---|---|
| Reflection Damage Multiplier | 0.2 |
Damage reflected back (0 = none, 0.2 = 20%, 1 = 100%, 100 = 10000%) |
| Evolution Reduction per Kill | 0.005 |
Evolution subtracted per enemy kill (0.01 = 1 percentage point) |
| Prevent Evolution from Nest Destruction | true |
When enabled, destroying spawners adds NO evolution |
| Show Evolution Changes in Chat | false |
Print evolution changes to chat (can be spammy) |
| Enable Debug Logging | false |
Log detailed messages to factorio-current.log |
Commands
| Command | Description |
|---|---|
/evolution-down |
Reduce evolution by the configured amount (testing) |
/evolution-get |
Display current evolution with full precision |
Why Use This Mod?
- Punishes breaches – Biters that break through your walls will destroy themselves in the process.
- Rewards defence – Killing enemies actively lowers evolution, making future waves easier.
- Customisable – Tune the reflection strength and evolution reduction to your liking.
- Lightweight – No tick-based overhead; the mod only reacts when damage or death occurs.
Compatibility
- Factorio 2.0.77+ – Fully compatible.
- Space Age – Fully compatible and verified.
- Multiplayer – Works in multiplayer; settings are global.
- Other mods – Uses standard API events (
on_entity_diedandon_entity_damaged). Conflicts are rare.
Credits
- Original idea: abregado
- Previous fixes: gearsgod
- Factorio 2.0 / Space Age rebuild and updates: Dabria
Support
Found a bug or have a suggestion? Report it on the Factorio Mod Portal with your factorio-current.log file attached.
Version: 2.9.8
Last Updated: 2026-07-24
Factorio Version: 2.0.77+