As you may know whenever Chen used to be viable it was his keg smash/fire breath build, then why use this build? I tested this build and found out that this is very streamlined and smooth gameplay. Great sustain, great mobility and you get more slows from you Q with this build and a surprising amount of damage. I think this is the best option for any 1v1 scenario aswell as you can drink, Q>W>E and drink, this will make the Q crit and you practically unkillable.