
I have no interest in playing a game
in which I find no CHALLENGE.
The Big Bang Theory Season 3, Episode 5

Maybe you need to CHALLENGE
your motor skills.
The Big Bang Theory Season 10, Episode 22

I see no other option than
to CHALLENGE you to a duel.
The Big Bang Theory Season 5, Episode 17

I always got stuck on
the first CHALLENGE--
The Big Bang Theory Season 7, Episode 3

Trivial even.
You want a real CHALLENGE? Try whores.
Game of Thrones Season 3, Episode 3