Donatello creates a remote-controlled robot turtle, Metalhead, to fight in his place.
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!!This episode provides examples of:
* AgonyOfTheFeet: Mikey attempts to stop Metalhead by doing a good old-fashioned GroinAttack. Cue Mikey briefly hopping around on one foot, before getting punched by Metalhead.
* AlwaysNight: Leo explains that the turtles don't go topside during the day.
* BallsOfSteel[=/=]GroinAttack: Mikey kicks Metalhead in the crotch, which not only fails completely, but also causes Mikey to damn near break his foot. Justified, since Metalhead ''is'' a robot.
* BigDamnHeroes: Donnie, complete with DynamicEntry, which is lampshaded by Mikey.
-->'''Mikey''': Bangin' entrance, dude!
* BorrowedCatchPhrase: Donnie yells "Booyakasha!" after Metalhead is defeated. Also lampshaded by Mikey.
-->'''Mikey''': Sounds weird when he says it.
-->'''Raph''': Sounds weird when ''you'' say it.
* BoringButPractical: Donnie's MartialArtsStaff has been broken and replaced more times than Donnie is okay with, as the others make fun of him for it. That said, the staff proves to be a highly useful weapon nonetheless against Metalhead and Donnie stops looking down on it.
* DeathByIrony: Not only is Metalhead taken down by his own creator, he's also destroyed by the very same weapon that Donatello's dissatisfaction with led to Metalhead's creation in the first place.
* {{Foreshadowing}}: Leonardo watches an episode of ''Space Heroes'' where Captain Ryan has to MercyKill one of his crew after a brain-like alien takes over his body. This foreshadowed Metalhead being taken over by one of the Kraang and Donatello defeating Metalhead by damaging it.
* FunnyBackgroundEvent: At the end of the episode, whilst Donatello is showing off his, erm, rocket-staff, in the background you can see Raphael get annoyed at Leonardo, and ''grab him in a headlock'' with Michelangelo trying to pull him off.
* InventionalWisdom: In hindsight, using a Kraang interface port for the top of Metalhead's head wasn't that good an idea.
* ItsAllMyFault: Donnie gets this at the end of the episode.
* HypocriticalHumor: Donatello chides Raphael for not thinking things through... while Donnie's trying to fit a Kraang droid's body into a manhole too small for it.
* KickTheDog: Raphael near the end of the episode, which directly leads to ItsAllMyFault as mentioned above. It's worth noting that Raph went out of his way to point this out in the first place:
-->'''Raph:''' Yeah. Not bad. Except for the part where you built that thing in the first place. And the part where it broke. ''And'' the part where it tried to kill us! ''AND'' the part--
-->'''Donnie:''' ''Okay''! I ''get it''!
* LetsGetDangerous: After Donnie spends a great deal of the episode catching flack about his fighting/stealth skills and his bo staff. You can tell the ''instant'' he gets serious.
-->'''Don:''' Just come ''get me!''
* [[MyFriendsAndZoidberg My Friends... And Zoidberg]]:
-->'''Donatello:''' Gentlemen... and Raphael.
* SmartPeopleBuildRobots: The premise of the whole episode.
* StalkerWithACrush: Donnie slips into this again by using Metalhead's camera eyes to ogle April. Too bad he forgot to mute the speakers.
* SubvertedTrope: Donatello is fully expecting Splinter to stubbornly stick to old ninja ways and oppose his plans to build a robot and is already halfway done ranting before he realised that Splinter said yes. Splinter points out that Ninjas by their very nature are always looking for new advantages were always on the cutting edge of technology to enhance their stealth.
* TookALevelInBadass: April is still no ninja, but she's learned how to take down a single Kraang droid by herself.
* WithCatLikeTread: Metalhead, being a massive metal turtle does not quite fit the silent remit of ninjitsu.
--> '''Leonardo:''' You guys want to double back? I think there was one car alarm we ''didn't'' set off.
* WontTakeYesForAnAnswer: Happens with Donnie and Splinter twice.
* YourMom:
--> '''Donatello:''' Hey, Kraang! The one who is called your mother wears the boots that are made for combat!
--> '''Metalhead!Kraang:''' The comment that is made by you shows ignorance of Kraang. The ones known by you as mother-
--> '''Donatello:''' Just come get me!
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