The four doors
You have reached Mt. Dedede, but King Dedede has prepared one final challenge for you before you can fight him. Four of the previous bosses have returned, behind four doors in the hall of King Dedede's castle. In order to fight him, you must defeat all four bosses. You can fight each boss in any order, but you must do it without running out of lives, as continuing will mean you have to start the challenge all over again.
Green Greens door
The pre-boss section is quite straightforward with only a few enemies. There is a particularly precarious section where you have to pass underneath a column while airborne without falling into the bottomless pit below. Past that is the door to Whispy Woods, blocked by a Gordo. You must jump over it and touch Kirby's doppelganger beside it to remove the Gordo, letting you enter and challenge Whispy Woods.
Compared to the challenges you've faced before, Whispy Woods should be a complete pushover. You can probably defeat him without taking any damage. As before, suck up the apples that he drops and spit it back at him to injure him. Defeat Whispy Woods and you will warp back to the main hall.
Castle Lololo door
The level starts off with a climb up a tower, then a wide open area filled with enemies. They shouldn't be too big of a problem for you. Jump up the platforms from the start, then float all the way to the right to reach the boss' door. Again, a Gordo blocks the entrance, and you must collect the dancing Kirby on the nearby platform to remove it.
You will fight Lololo and Lalala once again. The fight is exactly the same before, so take your time and fight them patiently so that you don't lose too much health. Suck up their blocks and spit it back at them to deal damage. Use the multiple levels to your advantage, preferably staying below them so you can jump up and attack them after they pass you.
Float Islands door
Watch out for the coconut that drops down immediately to the right of where you start. Compared to the previous doors, there is no chance of falling to your death here. Get to the right, then jump down to fall into a cave. Run toward the left, where you must carefully maneuver yourself across a path lined with spikes on the ceiling and the ground. Once again, a Gordo guards the door to the boss. Touch the dancing Kirby to the left of it to remove it.
Before you fight Kaboola, there's a cloudy section similar to Float Islands where you must collect the Mint Leaf. Your strategy for Kaboola is still the same, but you must be more careful when dodging her shots to conserve as much health as you can for the remaining boss fights. Keep shooting air puffs at her until she goes down, while swiftly dodging all of her attacks.
Bubble Clouds door
The pre-boss section of this door is a long fall filled with a lot of enemies. You don't need to deal with any of them. Just slowly float to the ground while avoiding all of their attacks to reach the boss' door without hurting a single enemy. This time, the Kirby doppelganger is floating in midair. Just touch it to defeat the Gordo and enter the door.
Kracko will be the toughest boss you'll face among the four, due to how much more erratic its attack pattern is. However, you should be able to fight him more effectively the second time around, now that you're familiar with his attacks. Again, suck up the Waddle Doos it creates and spit them back out at him to damage him. Avoid getting hit at all, since the final boss fight is almost about the begin. Once you beat the last of the four area bosses, you will be back at the hall. King Dedede's face will now be on the wall. Go through it to begin the final battle.
Final Boss: King Dedede
As the last boss in the game, King Dedede is no slouch. He has a lot more attacks than previous bosses, is quite fast and the projectiles he creates that you must suck up and spit back at him disappear very quickly. King Dedede is also very tough, with a whopping 10 bars of health. However, he can still be defeated, if you learn to recognize his attacks.
Most of the time, King Dedede will just run at you. He will then either do a diving tackle or try to inhale you and spit you out. You can dodge both of these attacks by simply jumping, but King Dedede can also perform a high leap the sends him all the way to the top of the screen. He creates two stars on either side of him when he lands, which is the most reliable way for you to hurt him. Whenever he does his leap, get out of the way and suck up one of the stars when he lands and spit it back at him to damage him.
King Dedede can also run at you while holding his hammer up. If you're grounded or close to the ground, he will swing his hammer down, creating a star. If you're in the air, he will attempt to hit you by jumping up high and swinging his hammer. The star created from the hammer blow can also be spit back at him, but doing so is trickier. You must weave in and out from King Dedede when he runs at you with his hammer up, so that when he attacks you are close enough to suck up the star that he produces while avoiding the actual attack. If you try to dodge the attack by taking to the skies, try to leave some horizontal room for yourself to evade Dedede when he jumps up after you.
Once you defeat King Dedede, he will be sent flying out of the castle. With the power of the five Sparkling Stars, Kirby inflates into a huge balloon, lifting Dedede's castle from the mountain. Kirby floats all over Dream Land, dropping the stolen food all across it. Enjoy the credits as Kirby floats past a beautiful sunset. Congratulations for clearing Kirby's Dream Land!
Meanwhile, a disgraced King Dedede lands next to a large notice, telling you that you can now excess Extra Mode! If you think the regular game just isn't hard enough, press , and at once to begin a new adventure...