Far Cry 1: Player Shadows Restored! (modding)
This made it into the YvesGuillemotFix, which is a collection of mini fixes and visual tweaks, based on vanilla 1.4, you can get it there if you want: https://mega.nz/file/X44EhD5K#IQM-NmQ...
I'm obsessed with player shadows in first person games, especially those early ones like Doom 3 with Stencil shadows! I did not create this effect, it always was in the engine but for some reason it was disabled. Re-enabling it required a bit of C++ trickery with the public SDK, especially to reach a good compromise between stability and quality (maybe I can do better but for now this looks good enough to me).
I did this so I would have more fun playing the game for the Realistic Deathless No Binoculars challenge that I'm still preparing :)