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Mud Is Thicker Than Water is the thirty-fifth episode of Ben 10: Omniverse.


At Undertown, Liam, along with Tummyhead and Sweet-Eels Sparklefunk, are seen blasting at Ben and Magister Patelliday who are riding on the Tenn-Speed. Patelliday notices that the thugs are using unusual technology and Ben transforms into XLR8. XLR8 chases down the thugs while Patelliday follows behind on the Tenn-Speed. XLR8 then manages to trick Tummyhead into shooting at Sweet-Eels' motorcycle and also takes down Liam and Tummyhead. The thugs, however, have XLR8 surrounded but Patelliday quickly arrives and takes down Sweet-Eels. XLR8 snatches the blaster from Tummyhead and punches him down. XLR8 transforms back into Ben and he and Patelliday watch as Liam gets away. Ben notices that the blaster looks familiar and Patelliday confirms that the weapons are top secret Plumber tech.

Back in town, Gwen is seen talking to Kevin and Rook telling them to enjoy the auto show. Kevin and Rook drive off and Gwen heads down into the Plumber Base. Gwen walks up to Max but is surprised to see her cousin, Lucy, instead. A flashback happens wherein 11-year old Gwen is talking to Max, who is about to tell her something. However, she is surprised to see Lucy disguised as him and Lucy says she is staying for a couple of months and promises to Gwen that she won't get mud on anything. Gwen notices Lucy wearing her shirt and notices mud on her hairbrush. The flashback ends and present Gwen wants to know why Lucy is there. Lucy says she has been working with the Plumbers for a couple of months and promises not to get mud on anything. Deeper in the Plumber Base, Ben is seen talking with Max wondering how the thugs in Undertown getting their hands on the Plumber tech. Max reveals that the Plumber tech has been disappearing for a couple of months and Patelliday concludes that they are being stolen. Max suspects a "mole" while Ben attempts to make a joke about it. Max tells Patelliday to increase security and tells everyone else to stay on high alert. Ben asks for Lucy's ID and Lucy presents him with a Plumber Badge which Gwen questions. Max says that Lucy is the first Lenopan Plumber and Lucy says she graduated early from Plumbers' academy. Lucy then says it would be funny that she could be Gwen's commanding officer but Gwen gets annoyed by this. Later, Ben and Gwen are having an conversation where Ben says that they haven't done anything together in a long time. Ben notices Jerry passing by and Magister Patelliday walks up to Gwen saying that janitorial services are complaining about the mess she left behind in the girls restroom. Gwen gets upset by this but it turns out that Lucy disguised herself as Patelliday. Ben laughs at this but Gwen isn't so amused. Even deeper in the Plumber base, Gwen walks down with Ben saying she wants somewhere to talk alone without Lucy. Gwen admits to Ben that Lucy "rubs her the wrong way". Ben and Gwen then noticed someone is around and begin to follow the sounds. They enter a room and the generator quickly starts to go haywire. Gwen transforms into her Anodite form as Ben transforms into Eye Guy. They both managed to stop the generator with Eye Guy freezing the pipes. Later, while some Plumbers clean up the damages, Ben notices that someone was tampering with the control panel and Gwen suspects a sabotage. Gwen then wonders where Lucy is.

At Undertown, Psyphon is seen pacing and Liam wonders if he's okay. Psyphon says he is not okay and says that the price he is paying the spy at the Plumber base is expensive. However, Psyphon notices high tech Plumber tanks pull up and quickly changes his mind about the price. Back at the Plumber base, Max, Magister Patelliday, Ben, and Gwen have noticed that the someone made off with several Plumber tanks. Ben and Gwen leave the room and Ben urges Gwen that Lucy has nothing to do with the theft of the Plumber tech. However, Gwen still think Lucy is behind the theft and says she is going to find out. Ben then gets a call from Rook telling him about the auto show. However, screaming is heard on the phone but Ben tells Rook that it isn't too bad until he hears blasters being fired. Ben quickly leaves while Gwen runs into Kevin and asks why he is there. However, it's just Lucy again and another flashback happens where a younger Lucy is asking Gwen about what Kevin is like. Gwen tells her that Kevin is a guy who thinks that he is cool because he is a bad guy. Lucy laughs and then teases about Gwen liking Kevin but Gwen rejects the theory. Back to the present time, Gwen groins angry towards Lucy. Later, Max is telling everyone that the Plumber tech is being moved off of the planet starting with the most dangerous one: the Anihilaarg. Ben, once again, cannot pronounce the name while Patelliday says it can, indeed, destroy the universe. Gwen thought it didn't work but Patelliday says that someone fixed it and Blukic and Driba are briefly seen pointing to one another. Ben appears beside Gwen but Gwen suspects it's Lucy. However, Ben explains himself and Gwen says it's Ben but Lucy reveals herself greatly annoying Gwen. At a large spaceship, the Plumbers are loading up the Anihilaarg onto the ship and Gwen confirms to Max that it is safely loaded up on the spaceship. The spaceship takes off but Psyphon and his gang are seen on jetpacks and plan on taking the Anihilaarg. Psyphon blasts a hole in the ship and tells his gang to get the Anihilaarg. Ben transforms into Astrodactyl and starts to destroy the Plumber tech that Psyphon's gang are holding. Gwen is trying to defend the Anihilaarg from the gang members and is not surprised that Lucy isn't not present again. Meanwhile, Astrodactyl is having no problems knocking down more thugs and Gwen even assists in knocking down more of them. Astrodactyl transforms back into Ben and notices the Anihilaarg is gone.

At a warehouse, Psyphon is in possession of the Anihilaarg while Liam comments on how great it is. Suddenly, a Plumber storms into the building calling out to Psyphon and Psyphon reveals that's the spy. The Plumber is angry that he was thrown off the spaceship during the raid and rips off the Plumber's suit revealing himself to be Gorvan. Gorvan knocks down a couple of Psyphon's thugs and grabs Psyphon threatening to crush him while Ben, Gwen, and the Plumbers arrive on the scene. Psyphon wants to know how the Plumbers found out where he was and it turns out that Liam is actually Lucy who was, in turn, acting as a spy and transforms into her Lenopan form. The Plumbers begin to blast at Psyphon's thugs and Psyphon tells his gang to destroy everyone. Lucy informs Magister Patelliday that Gorvan is the mole and Patelliday tells Ben and the others to get Gorvan. Ben transforms into Crashhopper and knocks down Tummyhead. He then takes down Thunderpig, Sweet-Eels, and another alien but Psyphon enters the battle with a Plumber Tank. Crashhopper dodges the blasts of the Plumber Tank and Gwen stops an escaping Gorvan and takes back the Anihilaarg. Gorvan attacks at Gwen but she easily throws him down. Meanwhile, Crashhopper manages to knock down the Plumber Tank while causes Psyphon to escape from it. He suddenly runs into his old boss, Vilgax, and backs away in fear. However, it's just Lucy and Crashhopper smashes into Psyphon sending him through a wall. Crashhopper transforms back into Ben and yells at Gwen for throwing the Anihilaarg. However, it's actually fake with Gwen fooling Ben. Back at the Plumber base, Gorvan and Psyphon are being taken into custody while Patelliday and Max revealed that Lucy was brought in to pose as Liam to find out who the real traitor was. Gwen admits she's wrong about Lucy and apologizes for her actions. Another flashback happens where Gwen is upset that her hairbrush his covered in mud and suspects Lucy of doing it. However, she finds out that Ben was to blame and begins to chase him down. Lucy, who thinks this is a game, runs after them.  Back in the present time, Ben gets another call from Rook where it seems a problem has risen. Ben says he is on his way and leaves the Plumber base. Gwen and Lucy are seen talking and Lucy says she would get Gwen back when she is commanding officer. Gwen laughs but nervously says that if Lucy is joking and chases after Lucy.

Noteworthy EventsEdit

Major EventsEdit



Aliens UsedEdit






Naming and TranslationsEdit



  • The title of this episode is a play on the proverb "Blood is thicker than water".
  • Astrodactyl makes a reference to Oprah Winfrey (...and you get a whip, and you get a whip, and you get a whip!).


  • The episode takes place before and during OTTO Motives.
  • Lucy shows her Lenopan form for the first time.
  • It is revealed that Lucy is the first Lenopan Plumber.
  • Gwen's conversation with Gorvan about having taken cotillion for three years and Gorvan looking confused is similar to her conversation with Ben of the same topic six years ago in Big Fat Alien Wedding.