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Disney Wiki

"Monster Arm" is the first segment of the third episode of Star vs. the Forces of Evil. It premiered on April 6, 2015 alongside "The Other Exchange Student".

On February 23, 2015, the episode was released early on WATCHDisneyXD.com, the WATCH Disney XD app, and Disney XD on Demand.


When Marco hurts his arm before a big karate tournament, Star tries to fix it with magic but accidentally turns it into a giant tentacle.


Marco is practicing for his Tang Soo Do tournament against Jeremy Birnbaum, a boy that Marco considers his rival due to his wealth. As Star watches Marco prepare, he accidentally breaks his arm. Worried that he will be unable to perform in the tournament, Star tries to look up a way to help him. She reveals that she has a giant spell book that can help them, but that it is difficult to get through as the previous want owners simply add to the book once they have mastered a spell. Nevertheless, she finds what she presumes is a bone fixing spell and instead imbues Marco with a giant sloppy tentacle arm, much to his horror. As Star tries to find a counter spell, the arm begins to uncontrollably smack away everything and impede Marco's every day rituals.

At school, Marco's Monster Arm beats up the local bully Lars who runs away crying. This act earns the admiration of his friends and fellow students including Jackie-Lynn. As Marco starts getting used to Monster Arm, Star continues to look through the spell book and finds the counter spell, but when she tests it on a plant, it blows up. As Marco heads to bed, Star continues to practice the spell all through the night until she finally gets it early in the morning. She runs over to Marco and discovers that he has been practicing with Monster Arm as well. When she offers the spell to him, he angrily rebuffs her as he believes that he has an advantage now and kicks her out of his room. Afterwards, Monster Arm begins to speak and convinces Marco to use him in the tournament while hinting at malicious intentions.

Ferguson, Alfonzo and a very sleepy Star attend the tournament and are surprised to see that Jeremy is an obnoxious eight year old. Marco arrives and proceeds to beat up Jeremy, but when Monster Arm announces his plan to devour him, Marco attempts to fight back to no avail. Ferguson and Alfonzo manage to wake up Star who uses her arm spell, but keeps missing and creates arms all over the room. Marco forces the arms to grab him and Monster Arm and Star successfully cures Marco with Monster Arm claiming that he will return. Jeremy is revealed to have planned to use gold knuckles for the tournament, leaving Sensei disappointed in the two. Marco apologizes, but worries about Monster Arm's return, though Star tells him that it is not an issue.


Additional voices


The Disney Wiki has a collection of images and media related to Monster Arm.


  • This is the first episode that shows Star wearing her hair differently.
  • Despite the Monster Arm's claim that he will return, and the episode ending with it hinting it, it never comes back for the remainder of the series.
    • Daron Nefcy revealed in a Reddit Q&A, that they did attempt to bring it back, but that they could not think of a way to do it. Though she has said that it is still in Marco and "might emerge one day".[1]
  • Glossaryck once again makes another, albeit silent, appearance before his actual introduction.


  • When Star finally gets the spell right, the hand had five fingers, while the characters in the show normally have four. Additionally, it appears right handed, but when Star is kicked out of Marco's room, it is suddenly left handed.
  • In the scene where Marco is fighting the monster arm, Star seems to be aware of the situation, even though at this point she should have fallen asleep.

International Premieres

External links

  1. "Monster Arm Question". Reddit (August 3, 2019).

External links

v - e - d
StarVTFOE Logo.png
Star vs. the Forces of EvilStar and Marco's Guide to Mastering Every DimensionComic Books
Star ButterflyMarco DiazPony HeadLudoRiver ButterflyMoon ButterflyGlossaryckFerguson O'durgusonAlfonzo DolittleJackie-Lynn ThomasJanna OrdoniaBrittney WongMr. and Mrs. DiazOskar GreasonMiss SkullnickTom LucitorLaser PuppiesJeremy BirnbaumBuff FrogBuff Frog's TadpolesMonster ArmPrincipal SkeevesPrincess SmooshyToffeeMeteora ButterflyMina LoveberryEclipsa ButterflyGlobgorHekapooOmnitraxus PrimeRhombulusLekmetKellyLove SentenceMariposa Diaz
Season One: "Star Comes to Earth/Party With a Pony" • "Match Maker/School Spirit" • "Monster Arm/The Other Exchange Student" • "Cheer Up Star/Quest Buy" • "Diaz Family Vacation/Brittney's Party" • "Mewberty/Pixtopia" • "Lobster Claws/Sleep Spells" • "Blood Moon Ball/Fortune Cookies" • "Freeze Day/Royal Pain" • "St. Olga's Reform School for Wayward Princesses" • "Mewnipendance Day/The Banagic Incident" • "Interdimensional Field Trip/Marco Grows a Beard" • "Storm the Castle"

Season Two: "My New Wand!/Ludo in the Wild" • "Mr. Candle Cares/Red Belt" • "Star on Wheels/Fetch" • "Star vs. Echo Creek/Wand to Wand" • "Starstruck/Camping Trip" • "Starsitting/On the Job" • "Goblin Dogs/By the Book" • "Game of Flags/Girls' Day Out" • "Sleepover/Gift of the Card" • "Friendenemies/Is Mystery" • "Hungry Larry/Spider With a Top Hat" • "Into the Wand/Pizza Thing" • "Page Turner/Naysaya" • "Bon Bon the Birthday Clown" • "Raid the Cave/Trickstar" • "Baby/Running with Scissors" • "Mathmagic/The Bounce Lounge" • "Crystal Clear/The Hard Way" • "Heinous/All Belts are Off" • "Collateral Damage/Just Friends" • "Face the Music" • "Starcrushed"
Season Three: "The Battle for Mewni" • "Scent of a Hoodie/Rest in Pudding" • "Club Snubbed/Stranger Danger" • "Demoncism/Sophomore Slump" • "Lint Catcher/Trial by Squire" • "Princess Turdina/Starfari" • "Sweet Dreams/Lava Lake Beach" • "Death Peck/Ponymonium" • "Night Life/Deep Dive" • "Monster Bash" • "Stump Day/Holiday Spellcial" • "The Bogbeast of Boggabah/Total Eclipsa the Moon" • "Butterfly Trap/Ludo, Where Art Thou?" • "Is Another Mystery/Marco Jr." • "Skooled!/Booth Buddies" • "Bam Ui Pati!/Tough Love" • "Divide" • "Conquer"
Season Four: "Butterfly Follies" • "Escape from the Pie Folk" • "Moon Remembers/Swim Suit" • "Ransomgram/Lake House Fever" • "Yada Yada Berries/Down by the River" • "The Ponyhead Show!/Surviving the Spiderbites" • "Out of Business/Kelly's World" • "Curse of the Blood Moon" • "Princess Quasar Caterpillar and the Magic Bell/Ghost of Butterfly Castle" • "Cornball!/Meteora's Lesson" • "The Knight Shift/Queen-Napped" • "Junkin' Janna/A Spell with No Name" • "A Boy and His DC-700XE/The Monster and the Queen" • "Cornonation" • "Doop-Doop/Britta's Tacos" • "Beach Day/Gone Baby Gone" • "Sad Teen Hotline/Jannanigans" • "Mama Star/Ready, Aim, Fire" • "The Right Way/Here to Help" • "Pizza Party/The Tavern at the End of the Multiverse" • "Cleaved"

Royal Magic WandDimensional ScissorsMagic Instruction BookStar's Notebook of Spells
I'm from Another Dimension Closing ThemeShining StarSpace UnicornAwesome FeelingToo Little Too LateWaiting for MeJust FriendsThe Ballad of Star Butterfly
MewniEcho CreekEcho Creek AcademySt. Olga's Reform School for Wayward PrincessesDiaz House
See Also