Yin Yang Yo! Season 2 Episode 37

It's shown throughout the episode that Earth animals/bugs can only speak with their respective animal noises, with either Yin, Yang, or Carl to translate what's needed for the audience to understand. However it seems that the Earth Monkey and Cockroach are able to speak English.

It's learned in this episode that it has been exactly 1 year (in the world of Yin Yang Yo) since the events of Beetlemania, and it also happens to be Lena's birthday, which happens to fall on the same day as real life T.V. star's Jason Earles' birthday!

Running gags in this episode: 1. Yin and Yang keep arguing over Lena. 2. Whenever Lena, Yin and Yang try to communicate with humans, nobody understands them. 3. Everybody is continually surprised to talk about Lena actually being a dog! 4. Jason Earles and Mitchel Musso have a rivalry with each other to determine whose hair is more awesome (at least until it's removed by Carl.) 5. Yin, Yang, and Carl continuing to be shocked over the way Earth versions of their respective animals are treated. 6. Every human being scared of the realistic looking Carl and his huge cockroach army. 7. Yin, Yang, Carl, and Lena transforming into realistic animals. 8. Carl accidentally insulting real world cockroaches. 9. Jason Earles and Mitchel Musso keep calling each other by their full names. 10. Yang being unable to hold his sword when his paws change.

It's discovered in this episode that Yin, Yang, and Carl are able to use their powers in our dimension on Earth, as well as in their own.

First time that Yin, Yang, Lena, and Carl have appeared as realistic versions of their respective animals.

It is both revealed that not only Lena is a dog, but no one in the show knew she was one.