The Great Gold Coin Rush
At the start of the episode, Mario, Luigi, Princess Toadstool and Toad run through the wild Wild West in a chariot pulled by Ostros while being chased by several Snifits and King Koopa. They grab Piranha Plants and aim them at Mario and his friends' chariot, but Mario instead grabs a Cobrat and uses it to attack King Koopa. After that, King Koopa shoots a fireball to destroy the ropes that are used to control the Ostros. This causes the Ostros to flee, and Mario and his friends later slide down a cliff. They later escape from their chariot. King Koopa notices them at the bottom of the cliff, and goes after them.
Toad then spots a giant Warp Pipe leading to an unknown area, and he, Mario, Luigi, and Princess Toadstool decide to enter it. King Koopa then tosses a Bob-Omb to destroy the entrance of the pipe. In the area under the pipe, Mario discovers a room filled with coins, and Princess Toadstool says it is the Lost Gold Coin Mine. Luigi is worried about getting out of the mine, though Mario says that they can dig a way out with shovels.
After digging out of the gold mine, they reach a town. The gang reaches a seemingly empty town. An elder then appears and introduces himself as Calamity Clam and reveals that the town is called Lonesome Mushroom. They later reach the assay office, where Toad puts all of his coins from the mine on the desk and calls for the assayer. The assayer turns out to also be Calamity Clam, and Toad asks him to tell them if the coins are real. He says that the coins are real, and yells out to miners outside as they look through the window. King Koopa heard the noise and prepared to approach Lonesome Mushroom.
Back in the town, many miners came to dig for gold. Toad is unhappy about this gold rush and claims that it is his fault, but he later gets suddenly captured by King Koopa, who invades the town and captures the miners. Mario, Luigi, and Princess Toadstool escape from the town while the townsfolk and Toad are being forced to dig for gold. Sometime later, they return to learn that the King Koopa, the townsfolk and Toad are in the gold mine. Meanwhile, Toad starts fighting with King Koopa in the mine, but he fails. Mario wants to obtain Fire Flowers to save the townsfolk, and Calamity Clam reveals that they have to get past the tomato sauce mine to reach the Fire Flower mine. Calamity Clam wanted to take Mario to the pasta mine for lunch, but Princess Toadstool forces him to go to the Fire Flower mine. When they arrive at the mine, Mario and Luigi touch two Fire Flowers and become Super Mario and Super Luigi.
Later, the Mario Bros. punch through a wall near the gold mine and frightens the Snifits with fireballs, but Bowser captures Princess Toadstool in the meantime, and leaves riding a mine cart. Mario, Luigi and Toad then ride on another minecart to save her. During the chase, they pass through tunnels and the Mario Bros. begin to lose their powers. They soon pull Princess Toadstool into their cart when reaching the tomato sauce mine. King Koopa crashes through a green wooden gate, and he instead goes through the right path while the brothers go to the left one, passing him. Both carts later collide and Bowser is launched towards a cactus, hurting him. In the end, Mario and his friends celebrate King Koopa's defeat back in the town.
Animation and continuity errors
Names in other languages