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The Celebi Egg glitch is a method to obtain Celebi in Gold, Silver, and Crystal. Due to the fact that it is impossible to obtain Celebi via standard gameplay, this is currently the only way to get Celebi in the Generation II games without a Nintendo event or using cheat codes. However, like most other glitches, it may corrupt the player's save data.
This glitch was first documented at Glitch City Laboratories. It was found by Paco81. There is another way to get Celebi; the "Celebi trick" (also found by Paco81), but these two glitches are slightly different.
This is only one known method of carrying out the Celebi Egg glitch and successfully obtaining the Celebi.
- The Egg - The player must get an Egg that will know Beat Up as its third move upon hatching. This can be done by training a male and a female Sneasel up to level 57. Both Sneasel need to have the same four moves in the same order, with Beat Up at position three. Because both parents have the same moveset, the offspring will share this moveset.
- The bad clone - The player must get a bad clone, a clone with a name made of only question marks (or, in some cases, blank), its level will be 0 and its gender will be different than the prototype's. If that Pokémon doesn't fulfill all those requirements, then it isn't a "bad clone" and it cannot be used for the glitch. This can be done by Pokémon cloning. The Box that is used for cloning must not be totally filled up at any time (otherwise the Box is unable to produce bad clones). Getting a bad clone is a case of luck and occurs sometimes during the act of cloning. The chance of getting a bad clone is at maximum if the Box has 15 to 18 Pokémon. Another way to increase the player's chances is by turning the game off after he/she selects YES, before any of the "SAVING... DON'T TURN OFF THE POWER." text appears.
- Last requirement - The player must get any five Pokémon (preferably weak, common or otherwise useless Pokémon). The easiest way to get them is to clone a Pokémon until there is a bad clone. Because getting a bad clone takes some tries, he or she will get five unimportant Pokémon as a positive side effect of the bad clone action.
- Step 1 - The player must first deposit the Egg into a Box. The five other Pokémon and the bad clone have to be in the party.
- Step 2 - The player must then go to the Day Care and ask the man to raise the bad clone. He or she should then take it back from him, and it will be a ?????.
- Step 3 - Next, the player must put ????? at the top of his or her party and go to the PC.
- Step 4 - Using the "Move Pokémon without mail" option, the player must move any Pokémon (preferably weak or common Pokémon) from a PC Box to the top of their party. Its name should become the name of its original Trainer. The player will now have 7 Pokémon in his or her party.
- Step 5 - Next, the player must go back to the Day-Care Man and ask him to raise the ?????. Afterward, he or she should return to the PC.
- Step 6 - Back at the PC, the player must deposit the first and second party Pokémon.
- Step 7 - Using the "Move Pokémon without mail" option, the player must move the Egg from its PC Box to the top of his or her party.
- Step 8 - Next, the player needs to deposit the next four party Pokémon, but not the Egg.
- Step 9 - Subsequently, the player should withdraw any Pokémon that he or she didn't use for the glitch.
- Step 10 - Having completed the set up, the player should walk or bike around until the Egg hatches into a Celebi. However, the Celebi is still unplayable.
- Step 11- The Celebi will hatch at level 0. Due to how the game handles Pokémon that level up in battle, the player must allow the Day-Care Couple to raise the Celebi to at least level 2. After this, it works like any normal Celebi.
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The reason why the player gets Celebi is the move Beat Up. In Generation II, both Celebi and Beat Up share the same index number: 251. This is not random and should work with any other move-Pokémon combination. Psychic, whose index number is 94, should result in a Gengar hatching, while Splash, despite being considered the worst move, would ironically bring about a Mewtwo, as both share index number 150. This glitch therefore should not cause any glitch Pokémon to appear, as there were exactly 251 moves in Generation II, though Ledyba would not be obtainable in this way, as Struggle is unobtainable normally as a move.
If the Pokémon used for breeding has no third attack, the Pokémon that will come out from the Egg (after the glitch) will be a "bad clone" of the glitch Pokémon #000 ?????. This Pokémon, like other "bad clones" cannot be seen by the PC, and hence cannot be deposited in the player's PC or released. There are only 2 known ways to release a "bad clone." One way is to trade it to a Generation I game. Upon arrival, it will become a Generation I original or glitch Pokémon, which may be released normally. The other is to use the PC in the lab on Stadium 2 where the "bad clones" will show up as Ditto or, sometimes, another Pokémon, allowing the player to release it.
If a wild Ditto transforms into the hatched ?????, the wild Ditto is no longer catchable by any kind of Poké Ball. Even a Master Ball will fail to capture it. If a Ditto is bred with the "bad clone" of ?????, the offspring will be another "bad clone", knowing only Transform.
The "bad clone" of ????? may evolve to a Nidoran♂. Possible levels for evolution are 37 and 62.
At Step 5 of the glitch the player asks a Day-Care person to raise the Bad Clone of ????? (000). That clone will not be taken back until the glitch is finished. After the glitch is finished, that clone will disappear from the Day Care, but on rare occasions, it is possible for that Pokémon to not disappear and remain at the Day Care. In that case the Bad Clone of ????? (000) will be transformed into a Bad Clone of ????? (255). That Bad Clone of ????? (255), similarly to the Bad Clone of ????? (000), cannot be released by the PC, but can still be traded to a Generation I game and released there. It mostly works the same way as the Bad Clone of ????? (000), but it has some differences with it, as it cannot evolve into a Nidoran♂, and if a wild Ditto transforms into the hatched ????? (255), the wild Ditto can be caught normally. Also it learns Ice Punch at LV17 and Egg Bomb at LV44 and it can learn different TMs and HMs from the Bad Clone of ????? (000), for example the Bad Clone of ????? (000) can learn DynamicPunch (TM01) which the Bad Clone of ????? (255) cannot.
The hatched Pokémon's item
The hatched Pokémon will hold an item depending to the fourth attack of the Pokémon used for the breeding. Both the item and the fourth attack share the same index number. For example, if the two Pokémon used for the breeding have the move Reflect as their fourth move, the hatched Pokémon will hold a GS Ball (or Teru-sama in Pokémon Gold and Silver). This is because both the GS Ball and Reflect have the same index number: 115. If the Pokémon used for the breeding have the move Whirlpool as their fourth attack or Beat Up, the hatched Pokémon will hold the glitch items HM08 or HM09 respectively. Neither of these HMs can be obtained in normal gameplay: they are filler items, and have no corresponding moves. If the Pokémon used for the breeding have no fourth attack, the hatched Pokémon will hold nothing.
Other effects caused by this glitch
Some of the Pokémon that are deposited in step 6 and step 8 may have their names, gender, level, or attacks changed. Some of them will become "bad clones" and some will remain normal Pokémon. Some of them will also have Pokérus.
When done incorrectly, the Celebi Egg glitch may also result in a lot of code read errors and Pokémon/character data becoming scrambled. Players may end up with numerous bad clones. Going to the POKÉMON screen and looking at the move option will bring up all Pokémon in your party, as usual. However, selecting a Pokémon and going to the MOVE option will reveal that a ????? is hiding at least 50-80 glitch Pokémon. All of these glitch Pokémon represent the game's code and cause multiple bugs. Therefore, by switching their moves, the game's data, such as music and Pokédex entries, can be altered. The names of these Pokémon vary from ? to random characters and their levels range from 0 to 255. The player's name will also change to a random glitch name. Similarly, the player's ID number will change. The player's original name might be given to Pokémon with many ? in its name, or the names of old player files and Pokémon, and is usually tossed around with junk data (example: ???????GOLD?).
The moves of the glitch Pokémon take data from other parts of the game code. As a result, they usually turn into jargon (example: TYPE/ A9_9[9990979599999999DBB999? ×4 or Waterfall, Waterfall Waterfall, Waterfall or Pay Day, Horn Attack, SonicBoom, Mud-Slap) or just -, and the move's PP will become more than possible or corrupt (ex.: 56/15, 1/35, 86/1). By switching moves around, it is possible to change any data in the game. Since the hidden list of Pokémon is occupying so much space, the game won't be able to load sprite data and the player won't be able to move. While changing moves around, it is easy to access the glitch dimension, or even delete all of the player's Pokémon.
This effect of the Celebi Egg glitch is very similar to the TMTRAINER effect in Generation I.