Celebi



Celebi is a plot-relevant Pokemon that was added in version 4.0. Celebi appears in Celadon Gym, both as an ally Pokemon and as a foe.

In the game, there are two different types of Celebi. One is a good Celebi from the future and the other is a present-day Celebi, whom is controlled by Mewthree. The future Celebi is maybe less powerful than the foe Celebi.

Ally Celebi
The good Celebi first appears in the cutscene for Celadon Gym. It came from the future to help you -- one year after the events of the game. Celebi knows the protagonist from Johto, which will also be saved by the main character. Celebi came to the present day to help himself from Mewthree's mind-control. This Celebi helps you in the level by healing your Pokemon with maybe Aromatherapy. In Rocket Hideout it went with the other Celebi back to the future.

Foe Celebi
The evil, mind-controlled Celebi is an enemy Pokemon in Celadon Gym. Like all the other Pokemon in the gym, it cannot be caught. It will attack your towers by using Solar Beam. If you see it coming, remove your Pokemon from the map until it is out of range as it is very powerful and is nearly impossible to defeat at the current level.

However, it is possible to defeat if you have either Charizards with Fire Blast, Butterfrees with Bug Buzz, Victini with Fire Blast, or a Gengar (a Pokemon with Roar, Whirlwind, or Dragon Tail may help as well so you can get more hits off it). Although the easiest way to defeat Celebi is probably using a pokemon that knows Perish Song. Attempting to defeat Celebi isn't recommended if you're trying to beat the level for the first time, as its Solar Beam can kill anything in two to five hits and will reduce your numbers.

Location
Celadon Gym- Cutscene, uncatchable- Boss, uncatchable- Ally, uncatchable

Although, if you have a Pokemon with transform (Mew or any other Pokemon with Transform) You can be Celebi!