It just changes the default headcrab into the one from the beta!
It just changes the default headcrab into the one from the beta! Now, just place the unzipped folder into your custom folder on any Half-Life 2 mod/game! Don't got a custom folder? Then make it! Also, if you're lazy, just read the read me.
Credit to Missing Information for making the beta half-life 2 headcrab textures readable by the modern-day engine!