You just have to build a range of decks, if you are the person that has the resources to do so. I have some brutal decks and I have decks that, as a johnny player are trying to do something inherently goofy, some decks that get better or worse depending on opponents. I also mostly try to play colours that are not heavily represented at the table just so we have a solution to everything.
Pioneer:UR Pheonix
Modern:U Mono U Tron
EDH
GB Glissa, the traitor: Army of Cans
UW Dragonlord Ojutai: Dragonlord NOjutai
UWGDerevi, Empyrial Tactician "you cannot fight the storm"
R Zirilan of the claw. The solution to every problem is dragons
UB Etrata, the Silencer Cloning assassination
Peasant cube: Cards I own