Bowser

Bowser is an antagonist in the Mario franchise. He has broken the 4th wall numerous times during these games.

Super Mario 64
The player fights Bowser 3 times during Super Mario 64. The third time you beat him, he is shocked that you have won and tells you to "keep that joystick smoking". He is saying that he knows this is a game and is congratulating the player for beating him. He says the same thing in Super Mario 64 DS.

Mario and Luigi: Superstar Saga
When the player defeats Cackletta's Soul, Cackletta loses control over Bowser and dies. However, when the Maio bros escape, Bowser does not and is flung at the glass.