Tie One On! (メガニウムＶＳフシギダネ！くさタイプのいじ！ Meganium VS Bulbasaur! The Nature of Grass Types!) is the 59th episode of Pokémon: Master Quest.
The battle between Ash and Macy is over and Ash wins, but the next battle will determine if he will or will not go to the victory tournament. He faces off against Jackson, a trainer from Twinleaf Town who has a Meganium like Casey. Will Ash be able to win this final battle of the elimination block?
Macy fights against Jackson, who enters in a dramatic way. Ash sees this is the guy he will fight against. Later, Jackson has Poliwhirl and Macy her Quilava as their final Pokémon. Quilava uses Flamethrower and Jackson goes to order Poliwhirl to fight back, but trips over his cape. Poliwhirl is defeated by Flamethrower, so Macy wins the battle. Brock sees Ash has to have at least a tie to advance to next round. If Ash were to lose, there would be one more round. Ash is determined to win the battle, so losing is not an option. Bulbasaur plays with Squirtle, as they have not seen each other in a long time.
As the heroes enter the center, Ash notices Jackson talking with Prof. Elm. Prof. Elm greets Ash and tells Jackson, who picked Chikorita, had it evolve into a Meganium. Ash wonders why he did not use in the battle against Macy. Jackson replies he thought he'd keep it for the final round. Jackson admits it was a while since he talked to them, so Elm lets Jackson know his family loves him. Meanwhile, Bulbasaur goes to get an apple for Squirtle. However, a Meganium also gets the apple, and, due to too much force, they split the apple. Squirtle goes to eat, but Azumarill, who got the other piece, throws it on Squirtle's head. Squirtle puts its glasses on for a fight, but Bulbasaur, who even gets slapped by Azumarill, tries to calm down the sides. However, Meganium uses Vine Whip to trip it over, so they all get into a fight.
Elm reports that Larvitar is doing fine at Mt. Silver. Suddenly, Ash and Jackson hear Meganium and Bulbasaur are fighting. They go outside to stop the fight, so Harrison has Miltank use Heal Bell to calm the sides. Jenny comes, as she heard a report of a Pokémon fight. Harrison convinces her that the Pokémon were practicing. Gary arrives and claims they were sparring. Jenny warns them they could lose points for such stunts and leaves. Ash thanks Gary, who responds that he needs as much help as he needs, else he wouldn't pass further, calling him an amateur trainer. Ash is enraged, so Harrison sees they are rivals. Meanwhile, Jessie and Meowth ask James to paint. He makes a symbol, pleasing Jessie and Meowth, who can make new fake badges to sell.
During the night, Brock analyzes Jackson, so Ash decides to use Pikachu and Cyndaquil, but wonders which Pokémon should he also use. Next day, Jackson and Ash battle. Jackson sends Azumarill and Ash Pikachu. Azumarill starts with Water Gun, so Pikachu dodges using Quick Attack. Pikachu uses Thunderbolt, which gets countered by Bubblebeam. Azumarill uses Icy Wind, hitting Pikachu. Azumarill uses Iron Tail, hitting Pikachu, who attaches to its tail and defeats Azumarill with Thunder. Jackson calls Azumarill back and sends a grey Magneton. Pikachu uses Thunderbolt on Magneton, hitting it, who retaliates using the same move. Pikachu uses Quick Attack, but Magneton evades and strikes back using Thunderwave and Tri Attack, defeating Pikachu.
Ash sends Cyndaquil, who dodges Magneton's Thunderbolt. Cyndaquil uses Flamethrower and misses. Mangeton uses Thunderwave, but Cyndaquil uses Smokescreen to dim the vision, confusing Magneton and hitting it with Swift. Cyndaquil uses Flamethrower, but Magneton uses Double Team, followed by Thunderwave. Using Tri Attack, Cyndaquil is also defeated. Ash calls Cyndaquil back and sends Bulbasaur. Magneton uses Thunderbolt, but dodges and retaliates with Razor Leaf. Magneton uses Double Team, so Bulbasaur hits the real one with Vine Whip. Magneton uses Thunderwave, which gets countered by Razor Leaf. Magneton tries to attack with Tri Attack, though Bulbasaur jumps using Vine Whip. Magneton fires Leech Seed, draining Magneton's energy. Bulbasaur uses Vine Whip, spinning Magneton and defeating it.
Jackson calls Magneton back and sends Meganium. Bulbasaur uses Razor Leaf, but Meganium uses the same move, managing to hit Bulbasaur. Meganium and Bulbasaur use Vine Whip, though Meganium pulls Bulbasaur and tosses it to the ground. Meganium uses Body Slam, but Bulbasaur dodges and uses Razor Leaf, hitting Meganium, who uses Vine Whip. Bulbasaur's Vine Whip tosses it up, but gets hit by Razor Leaf. Meganium uses Body Slam, but Bulbasaur manages to toss it away. Meganium hits Bulbasaur with Razor Leaf, who attaches itself to Megaium and attacks with Razor Leaf. Both Pokémon are injured and stand up. Bulbasaur uses Vine Whip on Meganium, who uses the same attack. However, neither side does dodge and take the hits. Both fire Solarbeam, causing an explosion. After the explosion, Bulbasaur and Meganium see each other and fall in defeat.
Ash praises Bulbasaur, as now Ash can advance to next round. Jackson congratulates Ash, even Meganium shakes vines with Bulbasaur. Macy also congratulates to Ash and admits she will cheer for him. Team Rocket are selling badges and have a feeling they will become rich. The heroes see the screen and see Harrison passed to next round. However, Ash is shocked to see he has to battle Gary. Gary thinks Ash's experience will be a short one once Gary beats him, making Ash furious.
The "Who's that Pokémon?" is Azumarill.
Brock told Magneton's Icy Wind stopped Pikachu's attacks, but the move was Thunderwave.