Japanese Title: Nibi Gym Battle!!
Original Airdate: April 29, 1997
US Airdate: September 14, 1998
Finally Ash makes it to Pewter City to challenge the Pewter Gym for his first badge, the Boulder Badge. As he makes his way to a Pokémon Center to get his tired Pokémon healed, he runs across a man named Flint who scorns the idea that Ash has any chance of beating Brock. Misty explains that Gym Leaders are far stronger than normal Pokémon Trainers.
After healing his Pokémon Ash faces Brock, but is soundly defeated. Ash is distraught by how easily he lost, but later runs into Flint again who explains that Brock is an exceptional trainer, and indeed could be an even better one if not for his particular life circumstances. He shows Ash that Brock has been taking care of his many, many younger siblings since his dad left to become a Pokémon Trainer and his mom died after that.
Ash feels for Brock, but is still determined to win. Flint takes Ash to a hydroelectric dam explaining that Ash can use it to enhance Pikachu's electrical attacks. Ash then moves on to the gym with confidence.
In he rematch Pikachu is able to defeat Brock's Geodude with ease, but struggles again with Onix. When a small fire started by one of Pikachu's earlier attacks sets off the sprinklers, however, Ash has the chance he needs to win, as Onix is very weak against water. Instead of attacking, however, Ash calls of the match, stating that taking advantage of the accident would not be a real victory. Brock then rewards Ash with a Boulder Badge for his kindness in not attacking Onix while he was hurt. Brock explains that he really wants to breed Pokémon instead of fighting them, but he is stuck with the gym since he has to care for his siblings.
Flint then shows up to reveal he is actually Brock's father and that Brock can journey with Ash to become an experienced breeder while he stays at home to care for his kids. Thus the episode ends happily.
- Brick Joke: In the beginning of the episode, we see Team Rocket digging a hole in the ground to trap Ash and company only to fall into that very same hole. They are conspicuously absent from the main story as the conflict is between Ash and Brock. But as the episode ends, Team Rocket suddenly makes their reappearance by digging out of the ground, only to be trampled back in by the unsuspecting twerps.
- Defeat Means Friendship: Brock becomes Ash's ally after his defeat, and goes onto become his best (human) friend over the course of the series.
- Disappeared Dad: Flint. He returns at the end of the episode, though he and Brock are still not on very good terms.
- Dub-Induced Plot Hole: In the English dub Flint claims Brock's mother is dead, while in the original she merely left home after being sick of complaining with his father. Possibly this was to prevent her from seeming heartless or neglectful, but the change caused problems much later on when Brock's mother shows up in a side story episode, and several episodes after that.
- Early Installment Weirdness: Ash gets the Boulder Badge despite forfeiting due to not being willing to win from a fluke, though unlike in other instances he was clearly going to win if he had not done so. The sprinklers making Onix vulnerable to electric attacks also counts. Also, Ash is prepared to leave Pewter City before Brock catches up to him and gives him the badge, meaning he gave up.
- When Onix has Pikachu in Bind, Ash attempts to use Pikachu's Poké Ball to call it back, but is unable to. While canonically Pikachu would refuse anyway, in the Generation I games, this can actually be done. Bind prevents call-backs and escapes beginning in Generation II, and still resists switches in battles in later Generations even with Abilities and Items that usually enable escapes and switches from the trap mechanic.
- Elemental RockPaperScissors:
- This episode mentions that Rock types are strong against flying, thus why Pidgeotto is ineffective against Geodude, and it demonstrates how poorly electrical attacks are against Rock Pokémon as well.
- This episode also demonstrates that elemental weakness extend to more than just Pokémon attacks, as Onix is hurt by being exposed to the water from the sprinkler system. Ironically this actually made Canon in the games with Soak, a move that can changes any type into a Water-type, and thus makes it possible for Pikachu to K.O. Onix with Thunderbolt.
- End-of-Episode Silliness: At the end of the episode, Team Rocket manages to dig their way out of the trap only to get trampled underfoot by Ash, Brock, and Misty running towards Mt. Moon.
- Eye Catch: The featured Who's That Pokémon? this episode is Onix.
- Honor Before Reason:
- Ash rejects Misty's offer to lend him a water Pokémon to use, since water Pokémon are much better against Ground and Rock types. Ash refuses because he wants to win under his own power. Since using an unfamiliar Pokémon is not exactly easy and takes trainer skill to do, it is debatable whether Ash's reasoning follows.
- After the sprinklers went off, Ash and Pikachu gain the rare opportunity to finally defeat Onix once and for all. However, when Brock's siblings try to stop Ash from hurting Onix (despite Brock's insistence to let the match continue), Ash decided out of respect for Brock's Pokémon to forfeit the match, saying that he had an unfair advantage and intends to battle Brock again in a fair fight. This is what ultimately earns him the Boulder Badge.
- House Husband: Brock is not married, but he is shown as being very good with domestic matters raising his nine younger siblings. He can sew and cook and solve disputes like a champ. This is related to his ambitions as a Pokémon breeder, he enjoys caring for pokemon and making food for them.
- Idiot Hero: Ash is once again shown as being ignorant of Pokémon type advantages, giving Brock and Misty the opportunity to explain to the viewers that birds are weak against rocks and rocks (though technically it's ground) are strong against electricity.
- Jerkass Façade: Brock acts stern as a gym leader, but as long-time fans know by now, he's in truth a rather sensitive guy.
- Lightning Can Do Anything: Ash hooks Pikachu up to a generator and runs it until it explodes, which somehow enhances Pikachu's electric power and allows him to damage Geodude and Onix.
- Out of Focus: This is the first episode to not feature Team Rocket in a major role since their debut, as they only appeared in the beginning and end of the episode. They didn't even interact with Ash and friends until at end where they get their faces stomped accidentally by the newly formed Power Trio.
- Parental Abandonment: Inverted; Brock's parent both leaving him is a major plot point, but the effect of the abandonment is the opposite of the Parental Abandonment trope. Normally absent parents are a way for young characters to get to journey off and have adventures on their own, but in this case the missing parents are the reason Brock can't leave home and have adventures.
- Pit Trap: Team Rocket dig their first pitfall trap at the beginning of the episode to catch Ash and Pikachu, but they had blended it with the terrain so well that they forgot where the trap was. When they try to locate the pitfall, Team Rocket end up falling into it.
- Promotion to Parent: A very straight forward example, Brock has to care for his younger siblings after both his parents leave. He is extremely good at it.
- Scissors Cuts Rock: Pikachu's new power-up is demonstrated by having him fry Geodude with electricity, an element he normally resists.
- Tear Jerker: In-Universe, Flint explains Brock's circumstances to Ash and Ash breaks into tears at how sad it is.
- Uncanny Family Resemblance:
- All of Brock's nine siblings look a great deal like Brock, as does his dad. When his mom shows up much later she strangely looks nothing like any of her kids.
- This is the first episode to introduce the idea that all the Nurse Joys are actually relatives that look identical and all have the same names and the same job.