Instructions
Dragon's Den
Defeat Clair, the Dragon-type Gym Leader in Blackthorn City. Her team is composed of two Dragonair, a Gyarados and a Kingdra. After you defeat her, she will direct you to the Dragon's Den, where you must pass a test to earn her Rising Badge.
Visit the Dragon's Den, a cave in the northern section of Blackthorn City.
Use Surf to navigate to the shrine on the opposite end of the cave. A group of elders will be waiting there to test you. Answer the questions during their multiple-choice quiz. Afterward, they will give you a Dratini if you have a vacant slot in your party and have obtained or defeated Ho-oh, the legendary phoenix Pokemon.
If you want to obtain additional Dratini while in the Dragon's Den, use a Good Rod or Super Rod to fish in the water. Occasionally, a wild Dratini will grab your line.
Use attacks to lower the wild Dratini's health, and then capture it in a PokéBall.
Safari Zone
Travel to the Safari Zone, which is northwest of Cianwood City.
Use the Object Arrangement feature to add 10 water objects to the swamp area. This will lure Dratini to the area.
Go fishing with a Good Rod to encounter Dratini. Throw Safari Balls to capture the Dragon-type Pokémon. Alternatively, you bypass step two by fishing with a Super Rod.
Game Corner
Go to Goldenrod City's Game Corner, which is in the center of the city, north of the Pokémon Center.
Play the Voltorb Flip game, which requires you to flip tiles without uncovering an explosive Voltorb tile. Continue playing the game until you win 2,100 coins.
Talk to the men along the side of the Game Corner interior to trade your coins for a level 20 Dratini. You must have a vacant slot on your team to receive the Pokemon.