To Master the Onixpected! (Japanese: してんのうシバとうじょう！Enter Four Heavenly KingsSiba!) is the 71st episode of the Pokémon anime. It first aired in Japan on November 19, 1998 and in the United States on October 11, 1999.
With only three weeks left before the Pokémon League competition, Ash, Brock and Misty head up to Mt. Hideaway to find one of the Elite Four Trainers. Ash and Brock hope he will teach them the real secrets of Pokémon training, but what they really learn is that Mt. Hideaway is the land of overgrown Onix!
With three weeks left until the Pokémon League competition, Ash has fallen behind in training. On the couch of Ash's home, Ash and Brock watch the Elite Four's Bruno battling a Trainer with his Hitmonchan. As Bruno commands a Thunder Punch, the TV is switched off. Misty chastises Ash for goofing off. Ash tells Misty they were studying the tape of Bruno. Brock adds that they were learning the "powers of Pokémon" despite not knowing what those power were. Ash comments that Bruno could train him to learn the power. However Brock and Misty lament that the famous Bruno wouldn't waste his time with them. Ash confidently states that if they knew how to find him then Bruno would definitely teach him. Just then, Delia enters, telling the group that Bruno may be at his secret training ground, on Mt. Hideaway. Ash jumps up and tells his mother not to make dinner as they are going up to Mt. Hideaway.
Now on their way to the mountain, Misty tells the group that Mt. Hideaway appears to be only 7 miles away. Ash and Brock, completely exhausted, convince Misty that she should rest. The group rest at a house where an old lady brings them food and drink. Ash asks her if she knows of a Pokémon Trainer named Bruno training around the area. The old lady doesn't recognize the name but tells the trio that Pokémon Trainers have been stealing her meatball kebabs. As Ash and Brock eat, a bunch of windchimes start rattling. The lady angrily tells them that the thieves must be back again. Push broom in hand the lady runs out followed by Ash and company. They see three hermits running off with sacks in hand. The lady gives chase as Ash recognizes the bandits as Team Rocket. As they are about to start their motto, Meowth pulls out a remote and speeds it up, leaving Jessie and James exhausted. After this they tell Ash that because they always get beaten by him they have decided to become hermits and live off the land. Meowth adds they're also living off the old lady's meatball kebabs. The enraged old lady gives Team Rocket a beating with her broom and the troublesome trio run away leaving behind the kebabs. The lady tells the heroes that the mountain is known for overgrownOnix; the area's fertile soil makes them grow larger. The lady assures them that, despite their size, the Onix are very gentle.
Continuing up the mountain, Brock comments that they have been walking for hours but haven't seen any sign of Bruno or any giant Onix. Ash notices what he thinks is a road, but Brock thinks it is instead tracks made by a really big creature. Suddenly an intense rumbling is heard and the heroes turn to see an enormous Onix heading their way. The Onix approaches as the three run for their lives. A man beckons them to jump behind a rock, which saves the group from being crushed and the Onix rushes by. The man asks if they are okay. The group turn to thank him and Ash and Brock are amazed to see Bruno, but Misty doesn't recognize the man. The three heroes begin trailing Bruno up the mountain, when Bruno asks if there is a reason why they are following him. Brock gets on his knees, and asks him to help Ash train for the Pokémon League. Brock motions for Ash to ask as well. Ash also kneels and ask for Bruno's help. Bruno agrees to help them as long as they are willing to do everything he tells them to do.
Their first task is to carry buckets of water. Brock theorizes that the task is to make them physically strong. Ash adds that it also helps inner balance and outer equilibrium before he trips, which soaks Misty. Their second task is splitting wood. Bruno tells Ash this is to give him a firm grip. Ash chops the wood successfully, though the rogue piece hits Misty in the face and knocks her off the rock she was sitting on. Task three is to carry heavy rocks up hill. Bruno tells them that this will teach them how to control their 'inner nature'. Finally Bruno asks Ash to peel the bark of a twig. Ash peels it perfectly. Bruno takes it and tells them the lesson is to always pack a fork when camping. Bruno breaks the twig in two and uses them as chopsticks. Ash is a little discouraged by this and Misty says she thinks all of Bruno's lessons seem phony. Brock denies this and is ready to prove Bruno is a great Trainer. Brock says that he will sneak up behind him and hit him with a stick, claiming Bruno should sense Brock and stop the attack. Brock envisions him doing so and goes behind Bruno and attacks full force. Bruno fails to detect anything and Brock strikes him hard over the head leaving a large bruise.
As Bruno recovers from the incident, he asks Brock and Ash if they really want to know about the secrets of Pokémon training. Brock and Ash eagerly reply yes. Bruno tells them there are no such secrets and the reason he was on Mt. Hideaway was to catch the biggest Onix he could find. Bruno says that it's no secret that to be a strong Trainer you have to catch strong Pokémon. These revelations leave Ash, Brock and Misty distraught. Team Rocket overhear the conversation and plan to catch a strong Onix so they can be as good as the Elite Four without having to do any Pokémon training.
Following the gigantic Onix tracks, Meowth believes that they have no hope of catching such a big Pokémon. Jessie and James reveal that they have an unexpected weapon to catch Onix. At the end of the Onix tracks, Team Rocket set themselves in wait of the Onix. The ground begins rumbling as an enormous Onix bursts from underground. The Onix is much bigger than they were expecting and Meowth suggests they forget the idea. Jessie stubbornly says that they came for an Onix and that's what they would get.
Ash, Misty, and Brock are heading back down the mountain when they hear a loud noise. They race off to the source of the sound. Meanwhile Team Rocket are blasting missiles at the giant Onix. The smoke clears and the Onix is completely unharmed and begins advancing towards them. Terrified the three run into a nearby cave. The Onix begins tackling the wall of the cave causing it to start collapsing. Team Rocket are shouting for help as Ash and the others arrive. To save Team Rocket, Brock sends out his Onix, Misty sends out her Staryu, and Ash chooses Squirtle. Brock orders his Onix to use Tackle, but it gets knocked back by the wild Onix's size. Misty tells Staryu to use Water Gun but it is largely ineffective. Ash orders Squirtle to use Water Gun too, and the combined water attacks cause the Onix to recoil from the cave. Team Rocket use the opportunity to run for their lives. The wild Onix recovers from the double Water Gun attack and uses its tail to hit Staryu and Squirtle and Brock's Onix before sending Team Rocket on their way. The Onix then notices the heroes standing on the ledge above. The Onix tackles the edge where they are standing, causing Ash to lose his balance and fall into right in front of Onix. Pikachu jumps down and uses his Thunder Shock attack, but Onix just shakes it off. Pikachu is about to try again before Ash grabs him telling Pikachu that electric attacks won't work. They huddle together awaiting Onix's attack. But before Onix can strike, a lightning-fast Bruno leaps in and carries Ash and Pikachu to safety. Bruno looks down at the Onix which is thrashing around. Ash and Brock ask him what Pokémon and attack he will use. Bruno states that he will not use a Pokémon.
Bruno jumps down and asks Onix why it is acting so violent. The Onix dives at him several times, but Bruno dodges its hits asking it why it is attacking him. Bruno then jumps on Onix's head. Onix whips his tail around, which misses Bruno and instead connects with its own head. Bruno requests it not to be afraid of him and asks it to let him know what it is feeling. He closes his eyes and concentrates for some time. He then starts feeling around Onix's body. Eventually he finds something between Onix's rocks. Asking Onix to bear with the momentary pain, he strains before pulling out a Sandslash. The heroes are shocked and Ash checks it on his Pokédex. Apparently the Sandslash was irritating Onix the whole time and causing it to act aggressively. Bruno lets the Ground-type Pokémon go and asks Onix if it wants to come with him. Onix accepts and Bruno catches it in a Poké Ball. He jumps back up to Ash, Misty, and Brock. He then tells them the true secret is for Pokémon and humans to care for each other like Ash and Pikachu. Both of them look at each other and start laughing. Bruno farewells the trio telling Ash he looks forward to facing him in battle. Ash and Pikachu laugh together as they are now one day closer to the Pokémon League.
This episode's title is formatted as To Master The Onixpected on the DVD menu of Australian DVDs.
When fighting Onix, Ash says that Electric-type attacks don't work on Rock types. However, they actually have no effect on Ground types (this confusion may stem from the fact that most Rock types in Generation I, notably with the only exceptions being the five Fossil Pokémon, were also Ground types).
The word ougi (奥義), or "esoteric techniques", is translated as "secret" in the dub.
Throughout the episode, dango is consistently referred to as "muskrat meatballs" and "meat kabobs".
In the original, Brock expresses his admiration of the giant Onix, while Misty tells him now isn't the time to act so impressed. In the dub, he says he'd like to study him, and Misty quips that maybe he can if they survive.
A running gag is present in the original during the training montage. After Ash douses Misty with water, and then launches a piece of firewood at her head, he says he "didn't do that on purpose" both times. When Ash later picks up a rock and starts falling toward Misty with it, Misty says "you're doing this on purpose after all!" as she runs away.
In the original, Bruno exposes his façade by making a pun on 奥義 (esoteric technique) and 扇 (folding fan), while in the dub he says the lesson is to always bring a fork when going camping. Also, Bruno's rice porridge is referred to as his "Bruno stew" in the dub.
In the original, Jessie tells Meowth that they have a secret weapon, and Meowth says that's just their usual bazooka. In the dub, she tells him they have something "Onix-pected", and Meowth says that joke is "Onix-cceptable".
In the last scene of the original, the Rocket trio pretends they're narrating a nature show, while in the dub they make rock puns instead.