Joker

Truly the height of modern aviation.

The Joker is a human from DC Comics.

The Joker is a clownish figure who chases people and sings songs about Batman.

Fiction

Sam Witwicky's first impression of Que's grapple gloves was that they'd be perfect if he was trying to escape from the Joker. Dark of the Moon (novel)

Voice actor: Mark Hamill (archive footage)

Joker laughed at something. Mission: Impossibly Awesome Marathon
As a group of carolers including Bulkhead and Megatron sang Jingle Bells, the Joker hijacked the song with a verse about Batman while blasting off on a Christmas tree. The Hub Carolers (Second spot)

The retail incentive cover of All Hail Megatron #1 was a parody of the cover of Batman: The Killing Joke.
Several panels from The Killing Joke were homaged in UK Transformers issue #187.
Lee Sullivan based his design for Galvatron on Jack Nicholson's portrayal of the Joker from the 1989 Tim Burton Batman film.^{[citation needed]}
Much like Batman over the years, the Joker has been voiced by many Transformers voice actors, which consisted the likes of Kevin Michael Richardson, Jeff Bennett, John DiMaggio, Frank Welker, Corey Burton, Richard Epcar, Troy Baker, Michael Dobson, Jason Spisak, Dave Wittenberg, Tony Hale, Alan Tudyk, Kevin Pollak and most prominently, Mark Hamill.