
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

You want a real CHALLENGE,
try keeping me from eating more of these.
The Big Bang Theory Season 10, Episode 22

We accept your CHALLENGE.
Name a time and place.
The Big Bang Theory Season 2, Episode 12

or a CHALLENGE to the system.
Money Heist Season 3, Episode 8