The tallest and oldest of the three Warner siblings on Animaniacs; the one who says "Hello nurse!" He's not as innocent as his younger siblings Wakko and Dot, so he's the one apt to draw the curtain down with "Good night, everybody!" when things veer too far into innuendo. As the name and the Animaniacs theme music imply, he's the fast talker of the group. Rather like a young Bugs Bunny; the very model of a cartoon individual.

And, of course, Yakko is voiced by the talented Rob Paulsen.