Fantastic Four #4, page 12, panel 4
Writer: Stan Lee
Artist: Jack Kirby
Uncredited Inker: Sol Brodsky
Uncredited Letterer: Art Simek
So, this is the first time that Johnny has full ignition following his traditional battle cry. I'm pretty sure that he has come to regret this specific instance, as mere seconds later he dropped the amnesiac Namor into the ocean, restoring his memory and setting him on a vendetta against humanity.
Check out our coverage of Fantastic Four #4 in our third episode: Super-Villain Cavalcade