That's what you think, buster.
2 seconds sound clip from Snagglepuss - Paws for Applause (S1E9).
You can hear this line at 00:06:47.290 in the Blu-ray version of the episode.
Quote context
[...]
- Heavens to smithereens! Dynamite!
- Cut! Ha ha ha! Ho ho he he he ha ha!
- What's so funny? Why the hilarious ha-ha's? Are you so fabulously rich you can afford to be sued?
- You don't understand. We ran out of film. Ha ha ha!
- You did?
- Yeah!
- Isn't that funny? Now we'll have to shoot the whole thing over again.
- Why not? You're a brave lion, aren't you?
- That's what you think, buster.
- Cluck-cluck-cluck cluckity-cluck-cluck-cluck. Cluckity-cluck and a err-err-err-err-err even.
- This castle belonged to the brave and noble King Arthur of whom history tells us much.
- In this room is the famous round table where he met with his knights.
- And that is King Arthur's chair.
[...]