Smoky Progg

The Smoky Progg is a hidden boss appearing only in the first Pikmin game. It can be encountered in The Distant Spring before or on Day 15. To find its resting place, take a good look at the area map. In the middle of one of the lakes is a group of islands that looks like a flower from above. Go to the center and you'll see a large egg resting on the center island. Walk up and make physical contact with the egg. Try lightly brushing against it and tapping it and it will rumble, then explode and release the Smoky Progg. This is an extremely dangerous creature, and wherever it goes it leaves behind a trail of toxic waste that instantly kills all Pikmin. Pikmin must be thrown on its face to damage it. It will run to the onions and stand underneath them, emitting shockwaves that instantly uproot nearby Pikmin from the ground, killing them as they rush to the Progg. After enough hits to its face the Smoky Progg will fry itself and melt into its own shadow. After the shadow burns away it will leave behind a bronze sphere, worth 100 Pikmin (the most of any enemy in the game or in Pikmin 2). If you don't kill it the day that you disturb it, it will be gone the next day. However, attacking it at all is unwise because it is such a deadly enemy and doesn't hold a piece of Olimar's Ship.

Trivia

 * Olimar thinks that this is a deformed larval Mamuta.
 * The bronze sphere might be the glowing center of the Progg- (possibly) its heart or even its soul.
 * When an action replay is used to view the data behind the game during gameplay, the light emitting from certain enemies like the Puffstool, Armored Cannon Beetle and Smoky Progg will not be seen. This makes the Progg appear extra strange, with no facial features whatsoever.

Pikmin:The After Years
Same way to kill as in Pikmin 1 except that it will occasionally summon Progglings and a line of poison. White Pikmin are immune to all its attacks.

Pikmin 4
In Pikmin 4, the Smoky Progg is the rarest enemy in game, only appearing once, only in the main game (it is not found in challenge modes 1,2, or 3, being the only enemy to do so) in Progg Cavern, a secret cave found on the pikmin planet after beating the game. White Pikmin and Green Pikmin should fight it it, because depending on what color it changes, it will use that element. EG: The Progg turns green. It will use an acid attack. If it turns purple, it will use a poison attack.It still will roam around, so keep other pikmin far away. It also appears one last time, hidden somewhere in a 4-P Battle room, where it's egg is hidden halfway in the wall.