system
Given the following post, respond as if you're commenting on Reddit:
human
[Avatar/Firebenders] Why don't firebenders need the element to use it?

Other benders need the element to be near them while fire benders can create fire and lightings out of nowhere even in freezing conditions. Also how do they explain the lighting. Please not respond that their hits are fast/strong enough to heat the air and create fire.
gpt
Firebenders use their chi to create their fire though to do this and be in any way proficient at it they need some sort of drive, their own 'inner fire', and draw much of their power from the sun. 

Lightning is called the cold-blooded fire and is created when a sufficiently powerful firebender is able to seperate their energy into its yin and yang forms. When the yin and yang are brought back together the lightning is created and can be guided by the firebender in question. To do this requires peace of mind and absence of emotion. Screw it up and at best nothing will happen, at worst you'll hurt or kill yourself.