This is my first mod. I made this mod for myself because it bugged me how Geralt's eyes didn't dilate during the dark. Luckily plasticmetal's amazing Modular Eyes mod exists, so I was able to have the alt eyes activate during the night. The thing is, people have to host their mods to be compatible with the Modular Eyes mod, and I didn't see exactly what I wanted in terms of dilated pupils. One of the mods Dilated Pupils Alt for Modular Eyes, also hosts alt eyes where the pupils fill up the entire eye, which is accurate if Geralt uses a cat potion. I however wanted the eyes to change from vertical slits to circles in the night/dark, so I went ahead and made this mod. I'd highly recommend using this mod alongside the Lore Friendly Witchers mod file Real Witcher Eyes. That means in daylight Geralt's pupils will be vertical slits, and in the nighttime/caves, Geralt's pupils will widen! I also tried to make the color of my eye texture the same as that of the Lore Friendly Witcher's eye file for a smoother transition. This mod took me a while to make this but now that I know the process, I think I can repeat it fairly easily, so if you want me to make a specific eye texture compatible with the Modular Eyes mod, I can try to do so.

There is also a version where the alt eye texture is the same as the main file, but the black eye texture is the iris completely filled up, which is what the cat potion does in the lore. 

Installation:
First of all MAKE SURE that Modular Eyes is installed. Then extract my file to the mods folder of the Witcher 3 directory. If it doesn't exist create it. Wait a minute, it should already exist since you downloaded the Modular Eyes mod first...right? I'd recommend using Witcher 3 Mod Manager, I've been able to install over 50 mods on my game with it. Finally, you can go to the Mods settings in the options main menu. There you should find Modular Eyes and there you can customize when you want the alternate eyes to pop up. For my setup, I made the alternate eyes show up whenever I was in the dark or it was nighttime. I set the black eyes to show up whenever my toxicity was high, similar to the Netflix Witcher show. These are only suggestions of course.

Check out my other mods here:
Customizable Colors for Sword Trails
Customizable Colors for Aerdondight Glow Effect
Master Sword from The Legend of Zelda
TW2 Triss Blue Retexture
No Trees No Collisions
Daedric Dagger Knife Replacement