Yin and Yang prepare to go on vacation. Coop returns and tried to warn them of The Night Master's energy escaping, but they ignore him until it's too late.

Coop's mom is throwing a "welcome back/thanks for saving the world all by yourself" party, and Yin and Yang are the only ones not invited. Meanwhile, three flunkies join together and try to get into The Night Master's fortress. However, they need the spare key, which the Night Master gave to Coop!

Yin and Yang are pitted against each other in a fight.

Yin takes credit for saving the mayor, without acknowledging Yang's help.

Yang's brain becomes controlled by a villain known as Mastermind.

Master Yo faces an old nemesis he has never been able to defeat.

Yin and Yang uses a magical bracelet to make fooplicates of themselves until Yuck returns.

Melodia the Aardvark Princess returns to claim Yang until Fastidous makes Yin mad with the Stink Aardvarks.

Carl casts an ugly spell on Yin and Yang after Yin insults Carl and calls him a "buglie".

Yin and Yang learn self-control at an institute, but its founder, Ultimoose, may have more sinister plans in store.

Yin and Yang get a lesson in cultural enrichment when a foreign exchange student from Redneckistan named Jobeaux shows up. Meanwhile, the Chung Pow Kitties return in search of a powerful Woo Foo artifact. Yin and Yang suspect that there is more to Jobeaux than meets the eye.

Master Yo is sick of Yin and Yang disrespecting him. Yin and Yang are sick of Master Yo treating them like babies. When young Kraggler switches ages with Yo (part of a diabolical plan), Yin and Yang are forced to babysit the three-year-old Yo, and he reveals how powerful (and bratty) he was as a child.

Yin and Yang attempt to defeat a half-human, half-bull monster.

Carl forms a league of evil with three other villains when they all rent an apartment together.

Yang endorses a toy line for money but doesn't realize that the toys are harmful to children.

Yin, Yang and some of their friends accept a free vacation to a mysterious island, not knowing that it's a trap set by Smoke.

Ultimoose and Yang search for an amulet that will give them all of the Night Master's powers.

Yin reluctantly goes on a date with Coop, and she falls under his evil spell.

Carl tricks Yin into eating seeds that make her doubt everything.

Mr. Pondscum realizes he isn't a goldfish but a polliwog.

Carl magically switches brains with Master Yo in an attempt to destroy the Woo Fo warriors.

Yin takes in some seemingly harmless green creatures as pets, but Yang believes they are dangerous.

Yin and Yang become addicted to a TV show about a superhero but learn they should focus instead on becoming heroes in real life.

Yang loses his emotions after he is zapped by Fred.

When Yang separates himself from Yin and Master Yo, he saves a robot, and they start to act like brothers. But Yin is feeling suspicious and jealous and discovers the robot is actually a spy made by Zarnot sent to destroy Yang.

Yang develops a rare tooth condition and could end up as dinner on Edna's table.

Carl traps Yin and Yang in a sitcom with a magic remote.

Yang receives a powerful artifact, but it's a skirt and he refuses to wear it.

Carl attempts to blot out the rays of the sun.

When Yang finds out that Master Yo knows a form of fighting known as Clown Fu, he wants to learn the various techniques for himself.

The Chung Pow Kitties are desperately trying to claim the Licking Stick in the Woo Foo Weapon armory as their very own.

Yin and Yang begin magic training at Camp Magic Pants and become involved in pranks that get them into trouble.

Yang takes a job at an amusement park that turns out to be anything but fun.

Yin and Yang attempt to prevent Carl from using a pair of magical slippers for evil purposes.

Yang casts a spell that makes him disappear and unable to be heard.

Yin and Yang are magically stuck together by Mastermind so they will learn to cooperate with each other.

Yin hosts her first slumber party but she drives everyone crazy with her strict schedule.

Badfoot tries to steal a powerful artifact from Master Yo.

Yin and Yang play a cursed video game, which requires them to keep dancing or die.

Yin and Yang's former enemy Yuck returns and claims to be a reformed rabbit.

Yin and Yang meet a seemingly sweet old lady who really wants to fatten them up and serve them for dinner.

Yin and Yang want to become bears, but an evil ranger tries to get them mauled by the animals.

Yang gets a pet but it runs away after he neglects it.

Yin tricks a clam into liking her so she can steal his jewels.

Zarnot creates a robot girlfriend for himself.

Yang seeks out a vigilante named Possum Panda, but he discovers solo crime fighting isn't all it's made out to be.

Yang resorts to talking to a dummy after Master Yo leaves town, which infuriates Zarnot.

Eradicus creates a monster that gains power by consuming everyone's fears, and Yin and Yang try to destroy it.

Yin and Yang compete with the Manotaur in a game of chance.

Carl disguises himself as a normal kid to stop Eradicus from carrying out an evil plan that would make everyone bad.

Yin and Yang are tricked into entering a dangerous car race.

Yuck causes Yin and Yang to swap personalities so he can weaken them and seize power.

Zarnot disrupts Master Yo's holiday plans.

Yin and Yang team up with different partners to fight a common enemy.

Yin and Yang tease a pizza-delivery man, so Master Yo makes them deliver pizzas on time or else become a slice themselves.

Master Yo goes to extreme lengths to get Yin and Yang to take fighting seriously.

Mastermind attempts to destroy the city while Master Yo is absent, so Yin and Yang assemble an army to fight him.

Carl tries to make Yang his evil minion.

Yin and Yang are tricked into starring in a movie that is actually a trap set by Eradicus to destroy them.

Master Yo's recliner is discovered to be inhabited

Master Yo tries to teach Yin and Yang how to prevent Ella Mental from reading their minds.

Yin searches for a rare wild beast to protect it from hunters.

Yin and Yang's dirty-laundry pile turns into a monster and escapes into town.

President Muffins enlists help from Yin and Yang in a bid to get reelected.

Yin and Yang throw a party, but Eradicus plans to crash it so he can destroy them.

Yin falls in love with Coop once again, but their relationship blinds them to Eradicus' plan to destroy the town.

Leena meets Jason Earles and Mitchel Musso when she lands in Earles' backyard in Hollywood, where the two friends argue over who has the best hair.

Eradicus tries to divide the Woo Foo army in order to conquer it. He then takes a vacation at a spa where Master Yo is staying, and the two enemies attempt to get along for the duration of their stays.

Yin and Yang search for their parents after Yin is drained of her aura and only a transfusion from a parent will save her.