In the first game, the yellow Onion is in the second area, the Forest of Hope. Take enough Red Pikmin to defeat the Bulborb north of where you start out. Then, knock down the wall and kill the Bulborbs, dismiss the red Pikmin, and go north. You should see a darkish yellow colored Onion in the ground. Approach it, and it will turn bright yellow and rise out of the ground, and produce a single Yellow Pikmin sprout which you can then multiply.
In the second game, the yellow Onion is visible immediately upon entering the third area, the Perplexing Pool, along with a few wild Yellow Pikmin. You will need Red and White Pikmin to reach them. First, head around the side of the stump where you see the Onion, where you'll find a scale puzzle. Once you get passed that, you'll see that the only way to where the Onion is has a wall raised with poison generators beneath it, and a Fiery Bulblax blocking the way to that wall. Use your Red Pikmin to kill it, and then use your White Pikmin to break down the gate and disable the poison generators. After that, all you'll need to do is whistle the wild Yellows.
In the third game, Brittany finds the yellow Onion immediately upon entering the third area, the Distant Tundra. She'll wind up in a cave where she'll find two Yellow Pikmin trying to light a light bulb, and three Pikmin sprouts in the ground. With all five, the light bulb will light, and the Onion will bloom and rise from the ground. Within the cave, there are enough pellets to generate twenty more Yellow Pikmin, for a maximum total of 25; you will need at least twenty to open the way out of the cave.
After collecting the 2nd half of the globe treasure found in the Awakening Wood, go to the Perplexing Pool.
Walk forward to find a cutscene showing the Yellow Pikmin.
Then continue to walk past the Yellow Wollywog, to a set of scales. Throw all but 1 pikmin up there. Throw the last pikmin, while standing on the lower scale, on to the higher one to be lifted up. Once there, kill the Fiery Bulblax, and break down the poison gate. Walk to the pikmin and whistle to them and Yellow Pikmin are all yours.
Five yellow Pikmin can be found in the giant stump in the middle of the Perplexing Pool. To get there, circle clockwise around the area to the stone scales at the back. Any Pikmin you cannot get up on the ledge can be left with Louie, since there is a bridge you can build to make a shortcut back to the Onions.
Before you can get to the yellow Pikmin, you will need to fight a flaming Bulborb, so be sure to bring some red Pikmin and you will have to destroy a poison gate so bring White Pikmin.
Blue Pikmin are found in the Awakening Wood. To get them and their onion, you need yellow Pikmin. Once you land in the Awakening Wood, go northeast. After crossing a bridge, you will notice an electric barrier blocking your way (after a little bit). Use the yellow Pikmin to break down the barrier, and five blue Pikmin will be waiting for you.
White Pikmin can only be gotten by throwing Pikmin into Ivory Candypop Buds (white flowers), which are found underground. The caves in which the flower are found are:
Pikmin are obtained by bringing back enemies or pellets to the Onions of the Pikmin. The Onions will then produce Pikmin sprouts, and as soon as they are plucked from the ground, they will be ready to fight.
To get Mushroom Pikmin, go to the Puffstool in the Forest Navel and let it spore your Pikmin. They will become Mushroom Pikmin. Mushroom Pikmin will try to kill Olimar, and other Pikmin will try to kill them, and they will eventually perish on their own from the spores, decreasing your overall Pikmin number. Mushroom Pikmin go back to normal if they are put in an Onion, the Puffstool dies, or Olimar shakes them off.
Collect the rest of the parts of the ship.
The Onion should have spit out a Yellow seed the next day.
Ask your spelling teacher
Five yellow Pikmin can be found in the giant stump in the middle of the Perplexing Pool. They are not easy to receive, however. A slight puzzle is located to the left of the stump that you must first solve, along with a hoard of enemies.
In pikmin 1, you must get to the Forest of Hope, then go right, destroy the wall at the end then approach the onion in the ground, and in pikmin 2, you need to get to the Perplexing Pool, then go left on the white trail, then go right at the end, then take your red pikmin and white pikmin and kill the fiery Bulblax, then destroy the poison dirt wall, then whistle the yellow pikmin off the tree.
After collecting the 2nd half of the globe treasure found in the Awakening Wood, go to the Perplexing Pool. Walk forward to find a cutscene showing the Yellow Pikmin. Then continue to walk past the Yellow Wollywog, to a set of scales. Throw all but 1 pikmin up there. Throw the last pikmin, while standing on the lower scale, on to the higher one to be lifted up. Once there, kill the Fiery Bulblax, and break down the poison gate. Walk to the pikmin and whistle to them and Yellow Pikmin are all yours.
Unlike the first Pikmin, Pikmin 2 does not involve a time limit. Thus, the game has a more relaxed pace than its predecessor.
Just keep reproducing them. Bring enemies or pellets back to the red, yellow, or blue Onion and either red, blue, or yellow Pikmin will sprout into the ground. Have Olimar or Louie press "A" on them to pluck them out. However, if you are looking for purple and white Pikmin, you need to go into caves. Some caves contain flowers on the ground which are called Candypop Buds. The Ivory Candypop Buds will produce white Pikmin sprouts when you throw any pikmin in them, and the Violet Candypop Buds will produce purple Pikmin. These can only be used a few times. If you are grinding, I recommend the Subterranean Complex.
Simply throw Pikmin onto its head. Yellow Pikmin are the best for this, since they can be thrown higher. It also helps to use Ultra-Spicy and/or Ultra-Bitter Spray.
No. White Pikmin made their first appearance in Pikmin 2.
Yes. The graphics in Pikmin 2 improved noticeably over those in the original Pikmin.
No. There are no cheats in Pikmin 2.
No, they did not exist at that time. Only red, blue, and yellow Pikmin are available in the first Pikmin game. There are only white and purple Pikmin in Pikmin 2. They have no Onions, and can only be found by tossing any Pikmin into purple or white Candypop Buds. These flowers can only be found in underground caverns, which were not present in the original Pikmin. The flowers disappear after a certain amount of uses, and thus only certain amounts of purple and white Pikmin can be attained at one time.
5, red, yellow, blue, purple and white leaf bulborbs may be included although they can't be kept in onions and are only found in dungeons