How to Get Celebi in "SoulSilver" Without a Special Event or Action Replayby Katherine Harvey ; Updated September 22, 2017
Celebi is one of several legendary-type Pokemon that Nintendo only made available through real-life promotional events. Like Mew, the first of this kind, the most common way to obtain Celebi is through using glitches or a cheating device like an Action Replay DSi. However, for those who wish to obtain Celebi legitimately in "Pokemon SoulSilver," there is no way through gameplay. A player has to either import it from an older version of the game where they've already obtained Celebi, or trade for it.
Obtain your Pokedex naturally through the story almost immediately after you start the game.
Go to Pal Park. It is at the east end of Route 221 in Sinnoah.
Speak to the Park Ranger in the Lobby. He will help you move your Celebi from your previous version of Pokemon to "SoulSilver."
Go to the top floor of any Pokemon Center. Every city has one. The top floor is the Union Room, and the Trainers in there will explain, then unlock trading for you.
Go to Pokemon Center in Golden Rod City. In the basement you'll find the Global Trade Station which will allow you to make trades with any player in the world. Pokemon traded for from outside your country will gain experience at 1.7 times the normal rate.
Go to the basement of any Pokemon Center in any city except Golden Rod City in order to make a trade on the local Wi-Fi network. Unlike on the global market, you will need the friend codes of the people you wish to trade with locally to be able to connect to their DS.
Haggle for Celebi. Celebi is a highly sought-after Pokemon and the demand far outstrips the supply. Be prepared to pay for it with another rare Pokemon as well as a number of rare items such as Master Balls.