Donatello creates a remote-controlled robot turtle, Metalhead, to fight in his place.
This episode provides examples of:
- Agony of the Feet: Mikey attempts to stop Metalhead by doing a good old-fashioned Groin Attack. Cue Mikey briefly hopping around on one foot, before getting punched by Metalhead.
- Always Night: Leo explains that the turtles don't go topside during the day.
- Balls of Steel/Groin Attack: 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.
- Big Damn Heroes: Donnie, complete with Dynamic Entry, which is lampshaded by Mikey.
Mikey: Bangin' entrance, dude!
- Borrowed Catch Phrase: Donnie yells "Booyakasha!" after Evil!Metalhead is defeated. Also lampshaded by Mikey.
Mikey: Sounds weird when he says it.
Raph: Sounds weird when you say it.
- Death by Irony: 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 Mercy Kill 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.
- Funny Background Event: 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.
- Inventional Wisdom: In hindsight, using a Kraang interface port for the top of Metalhead's head wasn't that good an idea.
- It's All My Fault: Donnie gets this at the end of the episode.
- Kick the Dog: Raphael near the end of the episode, which directly leads to It's All My Fault 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!
- Let's Get Dangerous: 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!
- My Friends... And Zoidberg:
Donatello: Gentlemen... and Raphael.
- Smart People Build Robots: The premise of the whole episode.
- Stalker with a Crush: Donnie slips into this again by using Metalhead's camera eyes to ogle April. Too bad he forgot to mute the speakers.
- Took a Level in Badass: April is still no ninja, but she's learned how to take down a single Kraang droid by herself.
- With Cat Like Tread: Metalhead.
- Won't Take "Yes" for an Answer: Happens with Donnie and Splinter twice.
- Your Mom:
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!