Nathaniel, or Nate, is a character in Cobra Kai.
He joins the Cobra Kai Dojo at first, but after realizing that Cobra Kai's ruthless antics are going too far, he switches Miyagi-Do Karate. Despite maintaining Cobra Kai's mentality when he first arrives at Miyagi Do, he is soon able to let go of that and becomes a part of Miyagi Do.
From what we know about him, Nathaniel is an impressionable, foul-mouthed nerdy child. Even after joining Miyagi-Do in season 2, he has trouble letting go the Cobra Kai creed of "Strike First. Strike Hard. No Mercy." nor does his training limit his aggression as seen when he fights Bert. However he does show prominent skill in Karate, as shown he was able to overpower and pummel Bert without the need of his glasses to see.
In season 3, he helps out with the fundraiser for Miguel's surgery. However, after the Cobra Kai's take the money from the fundraiser which Nathaniel was holding on to and beat him up, Nathaniel complains to Sam. Later on, when Sam attempts to get Miyagi Do and Eagle Fang to form a truce, most disagree, with Nathaniel and Bert trading insults, though everyone eventually agrees. The day after the truce and fight with Cobra Kai, Nathaniel is shown to be friendly with Bert.
He joins the Cobra Kai Dojo shortly after Cobra Kai's success at the All Valley Karate Tournament. However, after Daniel LaRusso, the sensei of the rival Miyagi-Do Karate Dojo confronts Cobra Kai's sensei Johnny Lawrence about trashing his dojo, Nathaniel likely realizing that Cobra Kai's ruthless teachings have gone to far leaves the dojo along with Chris and a numerous other Cobra Kai students.
At Moon's party on the last night before the first day of school Nathaniel is shown dancing and the crowd cheers for him. When the cops arrive Nathaniel presumably runs away like the rest.
When the school brawl occurs the next day, Nathaniel fights Cobra Kai student Bert. He gains the upper hand at first. However, after some time Bert is able to break his glasses. An angry Nathaniel then tackles Bert and starts punching him, but a security guard then picks up Nathaniel and takes him and Bert away (possibly to the principles office).
Bert collects the money for the fundraiser to fund Miguel's surgery. At the end of the day however, Hawk, Mitch and two other Cobra Kai's, corner Nathaniel, take the money so they can give it to Miguel, and beat him up. After being beaten up, Nathaniel and the other Miyagi Do's show up and Sam's house, where he tells her what happened. This prompts Sam to re open Miyagi Do and train with Nathaniel and the others.
Later on, when Sam attempts to form a truce between Miyagi Do and Johnny's Eagle Fang Karate Dojo (Counter dojo to fight against Cobra Kai), most initially disagree, with Nathaniel and Bert insulting each other. However, everyone soon agrees. During the brawl with Cobra Kai shortly after, Nathaniel is seen aiding Miyagi Do and Eagle Fang, but isn't necessarily seen fighting. While he struggles and his side starts to lose, they eventually win, partly due to Hawk defecting and siding with the Miyagi Do's.
The morning after the fight, Miyagi Do and Eagle Fang merge into one and are training at Miyagi Do, with Johnny and Daniel as their sensei's. Now, befriending each other, Nathaniel and Bert high five each other.
Nathaniel appears as a boss in the video game Cobra Kai: The Karate Kid Saga Continues at the Weinberg studios in the Cobra Kai side of the story as Johnny confronts his step father Sid Weinberg where he casts him for a movie before fighting him.