It's luck, as you fight you'll find a monster that drops a mysterious egg. You either go in to the top left corner, left click the egg and relese Articino, you need to weaken it and capture it. Or you could do the same in the bottom right for Moltres, but i don't know how to get Zapdos.
The mysterious egg is an item in Pokemon Pearl version. It will hatch into either a Happiny or a Riolu.
Togepi....i think
If you get the item from the shop in the bottom left of the map and give it to an electabuzz it will evole into a new Pokemon :) Also if you get a mysterious egg then take it to any of the corners and use it and that legendary bird will pop up (Ex: Fire Corner= Moltres)
a random Pokemon will hatch
You have to have Pokemon Ranger and do the quest for the Mysterious Egg. Then you can transfer the egg over to Diamond, Pearl, or Platinum.
you need a Pokemon egg, then go to fire Pokemon base... there is a little lava plate... hatch the egg there to get moltress..... you have to go water place and wind some ice plate.... hatch there to get articuno by: xions
you need Pokemon ranger shadows of alma finish the game you get wonder egg (or manaphy/mysterious egg)but its blue trade it to dpp then voila you have a manaphy egg
it takes 5100 steps to hatch the larvesta egg given to you by the Pokemon ranger.
A Pokemon egg have no name, but when the egg hatches you can give the Pokemon a nickname.
route 2 in the kanto world they are very low level or evolve a pichuwhich you may ger in the mysterious egg
A Manaphy is not available in the wild in the Pokemon world. You must trade a Manaphy Egg from Pokemon Ranger.
You can purchase an item called "Nurtured Penguin Egg" that allows you to summon "Pengu".