Originally posted by ShadowFyre
The cartoon one had a green beam not sure if they explained
They actually did!
Godzilla in the cartoon is the single surviving baby we see at the end of the movie. But Nick, the main character from the show was the one who found him and hatched him, so Godzilla sees Nick as his mom, which lets Nick control him and use him to fight evil monsters in exchange for being his buddy and snuggles and feeding him tons of fish every day.
Unlike GINO, this Zilla can't just spawn eggs, but he does have the atomic breath. That isn't explained why, but it's pointed out they're different.