6 day run

A 6 day run is a challenge run of in which the player collects every part of the S.S. Dolphin in the minimum number of days possible, which is six. Few players are able to do this, as it is very difficult and requires extreme skill in managing the Pikmin. Many tricks are used in this run to help the players collect the parts faster, or in a different order. There are no limits on Pikmin deaths, though it is possible to perform this run in conjunction with a zero death run.

Outline
Different players may have slight differences in what they do throughout the run. Below is a general strategy outlining on what to do on each day.

Day 1

 * The Impact Site:
 * Grow 25 flower Reds.
 * Collect the Main Engine.

Day 2

 * The Forest of Hope:
 * Discover and grow 15 Yellow Pikmin.
 * Get your Red Pikmin count to 77 or more.
 * Collect the Eternal Fuel Dynamo.
 * Collect the Whimsical Radar.
 * Collect the Extraordinary Bolt.
 * Collect the Nova Blaster.
 * Collect the Shock Absorber.
 * Collect the Radiation Canopy.
 * Collect the Geiger Counter.
 * Collect the Sagittarius.

Day 3

 * The Forest Navel:
 * Discover and grow at least 40 Blue Pikmin to carry the Anti-Dioxin Filter.
 * Collect the Automatic Gear.
 * Collect the Space Float.
 * Collect the #1 Ionium Jet.
 * Collect the Omega Stabilizer.
 * Collect the Gravity Jumper.
 * Collect the Analog Computer.
 * Collect the Guard Satellite.
 * Collect the Anti-Dioxin Filter.
 * Collect the Libra.

Day 4

 * The Distant Spring:
 * Collect the Repair-type Bolt.
 * Collect the Massage Machine.
 * Collect the Interstellar Radio.
 * Collect the Gluon Drive.
 * Collect the UV Lamp.
 * Collect the Zirconium Rotor.
 * Collect the Pilot's Seat.
 * Collect the Bowsprit.
 * Collect the Chronos Reactor (using an out-of-bounds glitch).
 * Collect the #2 Ionium Jet.

Day 5

 * The Impact Site:
 * Collect the Positron Generator.
 * Grow any Pikmin you need. (If you visit The Impact Site on day 4, be sure to leave with over 90 Blue Pikmin for The Distant Spring.)

Day 6

 * The Final Trial:
 * Defeat Emperor Bulblax.
 * Collect the Secret Safe.

10 days
The first few low day runs of the game completed it in ten days. No ship parts were obtained with unintended Pikmin types. Here's the general outline of such runs:
 * 1) Day one on the forced tutorial at The Impact Site.
 * 2) Day two at The Forest of Hope, where Yellow Pikmin are found, and four parts that don't require Blue Pikmin are recovered.
 * 3) Day three at The Forest Navel, where Blue Pikmin are found, and five parts are recovered.
 * 4) One day is spent returning to The Impact Site and recovering the Positron Generator.
 * 5) One day is spent on the rest of The Forest of Hope.
 * 6) One day is spent on the rest of The Forest Navel.
 * 7) One day is spent doing half of The Distant Spring.
 * 8) One day is spent continuing The Distant Spring.
 * 9) One day is spent finishing The Distant Spring.
 * 10) One day is spent on The Final Trial.

9 days
Some time after, "Sess" discovered some improvements to the route, like using bomb rocks on the Zirconium Rotor's gate, and 9 day runs became possible, removing one of the three days needed on The Distant Spring.

8 days
In July of 2011, "TTR010" managed to complete the entirety of The Distant Spring in a single day. This was due to a more optimized route, and the discovery of a glitch that allowed Olimar to get pushed by a Spotty Bulbear through the terrain and pop out-of-bounds, in the section of the area with the UV Lamp. With this, the player could take Olimar and some Blue Pikmin through a high ledge out of bounds that leads all the way to the Chronos Reactor, without the need to use the Golden Candypop Bud.

7 days
After The Distant Spring, the largest area, having been completed in one day, runners started considering shrinking the two other big areas into a single day. Most notoriously, "xHaii" and "Himajin". Both areas, like The Distant Spring, had a lot of tasks to complete in a single day, so routing was essential. The Forest Navel had potential, though The Forest of Hope had one critical stopping point: some ship parts require Blue Pikmin to be obtained, and Blue Pikmin cannot be unlocked until a later day.

Eventually, better routes were developed by both for the two areas, and "Himajin" managed to complete The Forest Navel in a single day in a run, becoming the first player to complete a 7 day run.

6 days
During the studies that made a 7 day run possible, The Forest of Hope had been found to be completable in one day, but it had to be done on day 3, and with many Red Pikmin. This exploited a few mechanics in order to obtain the Radiation Canopy, Geiger Counter, and Sagittarius. Runners continued investigating the area, and eventually found ways to overcome them all without needing Blue Pikmin. The strategies were optimized further and further with time.

Like the 7 day run, "Himajin" managed to be the first player to complete the game in 6 days, on 30.

5 day run problems
Each area must be entered on a different day, and since there are five areas, the likely absolute minimum amount of days is 5, unless some exploit is found that can change the way day progression works. Besides that, the only thing currently stopping a 5 day run from being possible is the fact that the player needs to spend two days on The Impact Site: one for the forced tutorial on day 1 with the collection of the Main Engine, and one to collect the Positron Generator. Even if it were possible to collect the Positron Generator on day 1, doing so will end the day, which means the player will still have to return some other time to get the Main Engine.