Basically, What is Qi, what do you do with it, and how do you get it? Thank you.

Its the sum amount of games you play.
And some items need X amount of qi.

;)

Basically Qi works like experience points (EXP).

However, instead of only earning experience when you win a game, you earn Qi every game you play. Winning games is not necessary in order to earn Qi. Like Boonana mentioned, some items are Qi-restricted... which means that you can only buy them if you got the Qi (Example: You can only buy demon if you got over 20000 Qi).

Unlike tc you're able to earn Qi in all of the servers ingame.

Awesome, you guys rock. Thanks.

Sure thing man, you're welcome