The Cartoon Network Action panel on Sunday of the San Diego Comic-Con made a special announcement in regards to the future of Ben 10 and Generator Rex. The production crew behind both shows were in attendance and the panel was moderated by Yuri Lowenthal, the voice of teenaged Ben Tennyson. This Thanksgiving, Ben 10 will be making a guest appearance in a special, extended episode of Generator Rex. The special will be dubbed Ben 10/Generator Rex: Heroes United. Footage was shown from the special where Ben appears to enter Rex’s universe from a portal and is mistaken as an Evo monster. Rex and Ben will fight before later teaming up. Ben and his alien avatars will be drawn and animated in the Generator Rex art and animation style. One of the early parts of the footage reel also shows Rex coming up with a “theme song” that sounds a lot like the original Ben 10 theme song in the show’s first season.