Who is really terrible at CHESS.
The Big Bang Theory Season 11, Episode 15
...if I could add a third
new CHESS piece.
The Big Bang Theory Season 4, Episode 22
I have invented
a new CHESS variant
The Big Bang Theory Season 12, Episode 17
In 4-D CHESS...
No.
The Big Bang Theory Season 7, Episode 1
Obviously, you're not well suited
for three-dimensional CHESS.
The Big Bang Theory Season 1, Episode 11