Fireworks:
Press Down on the crosspad to lay down on the ground. After this up to 4 pikmin will pick you up and carry you to one of the onions. You will then be lifted up like a dead enemy or a pellet. The onion will then reject you and drop you back to the ground, but will give you a fireworks display.
(supplied by: Serial Thriller)
Onion locations:
The red onion you will find on the impact site.
The yellow is on the forest of hope.
The blue onion is on the forest of lavander.
(supplied by: administer)
Get a pearl:
Go to the Impact site and go to the circular stump. Then fall off to the right, there are some bomb-rocks. Order your yellow pikmin to pick them up and get on the circular stump and keep going forward. There will be a rock wall, blow it down with the bomb-rocks. Once inside you will see what resembles a giant clam. Throw your pikmin in its mouth and calling them back. Eventullay you will get a pearl, it is worth 50 pikmin!
(supplied by: pats_angel)
How to defeat King Bulbax:
Let me warn you, it's not easy. First, break down the gate, and DON'T wake Bulbax up or you're busted. Break down the other gate and you'll see two dirty inhalers full of bombrocks! Collect them all and THEN wake him up. Put one or two yellows with the bombs in front of the beast. He'll lick them up and the bombs will explode and leave him frozen for a minute, throw the reds on his face like a teen with acne. If he recovers, retreat and get another yellow with bomb. Repeat until dead, Pikmin extinction, or Olimar is down.
(supplied by: Yugikatchum)