These are a number of glitches that exist in the Pokémon games.
This page lists several and details how to perform them.
WARNING/DISCLAIMER: FAILURE TO PERFORM A GLITCH CORRECTLY MAY CAUSE
GAME DATA TO BE ERASED. I AM NOT RESPONSIBLE FOR ERASED SAVE DATA.
Red/Blue/Green: MissingNo./▄█ 'M ▓▒ (Infinite Items): Put an item
that you wish to duplicate in the
sixth slot of your pack. Visit the guy in Viridian City who
teaches you how to use Poké Balls. Say No to his question about
being in a hurry. Fly to Cinnabar
Island. Use Surf on the east coast until you run into a wild Pokémon. It
will either be a very high-leveled Pokémon, MissingNo., or ▄█ 'M ▓▒. Select Run
in the latter two cases; in the former, feel free to make an
attempt to capture it. Afterwards, check your
items. The sixth slot will have the item name, a glitch symbol and the
number, like this: "Rare Candy ×✰4". What
actually happened was 128 of your given item were added unless
you already had at least 128. Thus, the maximum is 255. Try this with Master Balls
and Rare Candies to level up fast and catch Pokémon very easily.
A word of warning: This cheat messes up your Hall of Fame. In
addition, if you
catch Missing No. or ▄█ 'M ▓▒, you may
permanently destroy your save data.
Red/Blue/Green: Glitch
City: First, go to the Safari Zone. Enter by saying "Yes" and paying the
500 Poké. Save once you enter. Press Select, Start, A, and B
simultaneously to reset the game or turn the system off and on. Load your file. Attempt to exit
and say no. Do this until the guy says, "Welcome to the Safari
Zone…". Say No. Exit the building. Fly to Cinnabar Island. Surf
the east coast until he calls you over the intercom. Note: you
must be on the east coast when the timer goes off. Exit the
building. You have just arrived in Glitch City. To exit, use
Fly. Whatever you do, do not save, especially without HM 05 Fly
or a Pokémon that knows Fly. Try using the Town Map in Glitch
City!
Red/Blue/Green: Clone Pokémon: This glitch requires two games. Get the Pokémon to be cloned
on one game and a trash Pokémon on the other. Enter the trading room with the player 1 end of the
cable connected to the game with the good Pokémon. Select the two Pokémon specified. Turn off the
system with the game that has the good Pokémon at the start. Let the other game complete the trade.
Reset both games and the good Pokémon will have been cloned, with the trash Pokémon erased.
Gold/Silver: Clone Pokémon: Give an item to a
Pokémon. Go to Bill's PC in the Pokémon Center. Deposit the
Pokémon (and item) you want to clone. Switch to an empty box with
zero Pokémon in it. When it asks if you want to save, get your
finger on the power switch. Select Yes. After "Saving…" appears
turn off the power. If any part of "Don't" appears you may have
messed up. If you did it right the Pokémon and the item will get
duplicated. For example, try this with Ho-oh and a Master Ball.
Emerald: Clone Pokémon: First, deposit all but one Pokémon from your party into the PC.
Then save the game. Afterwards, withdraw five Pokémon (with items attached if wanted). Visit the
Battle Tower and request to enter. After selecting three Pokémon to enter, the game will appear
to get stuck for about two seconds, then it will ask you to save. Select No and reset the system.
You'll see the five withdrawn Pokémon in both your party and the PC. Warning: On occasion, the
clone will not work. On rare occasions, you may lose your Pokémon.
Diamond/Pearl: Clone Pokémon: Start by visiting the Global Trade Station in Jubilife City.
Be sure to bring in at least two Pokémon. Submit the Pokémon that you want to clone. Request
something uncommon or impossible, such as a rare first-stage Pokémon at level 100 or a last-stage
Pokémon at level 9 or less so it doesn't get claimed. Similar to the Gold & Silver version of
cloning Pokémon, you must turn the power off at exactly the right moment. When it says "Checking
GTS status", watch the icon in the bottom right. After the "hand" goes around 7½ times
(that's when it's pointing downward after seven rotations), turn the system off. When you restart,
log back on to the GTS and withdraw your Pokémon. It will also be in its original location.
According to many folks at GameFAQs, the new DS games may
even be the glitchiest Pokémon games yet, as at least eleven glitches have been confirmed. Several examples
are a cloning glitch (of course), pushing stones on the water, crashing the game, messing up the VS
Recorder, a Mystery Zone, and more.
Acid Rain: Acid rain refers to any time in
which both rain and sandstorm effects are running at the same
time.