What are the official rules to playing a pick-up game of 21?

[MJ Truth]

21/33 seems to switch up slightly depending on what region you're in; hell, it used to be different in separate parts of some cities.

 

[ROFL_GUY]

21 tips

Below 13 your shot gets tipped in your eliminated

After 13 you get tipped back to 13.

No 3s