- A Game Boy or Game Boy Color
- A copy of Pokémon Crystal
- A second Game Boy or Game Boy Color
- A copy of Pokémon Gold, Silver, or Crystal
Instructions:
1. Start a new game on Pokémon Crystal.
2. On the second Game Boy or Game Boy Color, load the Pokémon game that you want to use to trade with (Gold, Silver, or Crystal).
3. Start the trade between the two games. Ensure that the two systems are next to each other with their infrared ports facing each other. (Note: Your infrared ports may be covered by a plastic flap. Make sure that these covers are removed before trying to trade.)
4. On the Pokemon Crystal system, send over six level 5 or higher Pokemon to the second system.
5. Have the system receiving the Pokemon cancel the trade.
6. Turn off the system receiving the Pokemon.
7. Have the Crystal user go to the Pokemon Centre.
8. Have the user go into the backroom of the Pokemon Centre.
9. Talk to the first man on the left.
10. Press `A`.
11. Press `DOWN ` seven times.
12. Press the `B` button repeatedly until the trainer ID and Secret ID become one digit in length.
13. Turn the Game Boy Color off and on.
14. Go to the gate leading to the next town.
15. Save the game.
16. Hold the `B` and `SELECT` buttons and turn the Game Boy Color back on.
17. Walk down to where you would normally battle the gatekeeper and Celebi will appear.
18. Weaken Celebi and capture it.