u/Insominiac_21

I have Asus laptop which came with 120w charger. I want to know if a 100w USB-C charger can work with it or it will mandatorily require 120w/120w+ charger only.
I called exclusive store and they it will work but I want to know if occasional casual gaming will be supported or not, any battery harm?
Model- Asus vivobook 16x OLED k3605zf