FLASH STOCK ROM LG G2
In this video you can se how to enter into a Download Mode on your G2 and flash back the stock rom (.kdz file)
You can also fix your phone like this if its soft bricked, you cant enter TWRP etc. As long as you can enter Download Mode this is solution for you.
DOWNLOAD LINKS:
LG G2 drivers: https://goo.gl/A1R9Cq
LG Flashtool : https://goo.gl/q5Y2kq
LG G2 kdz files : https://goo.gl/moi2sv or https://goo.gl/cdqDB5