The Napsack is a part of the Exploration Kit in Pikmin 2. Its function is to provide a quick method of returning to the Pikmin Onions or the Research Pod, which is achieved by holding the X-button for a few seconds once it has been obtained. The Captain in control when it is used falls asleep, and any nearby Pikmin, up to a maximum of four, carry him to the Pikmin's associated Onion, a minimum of just one being required. This may seem like a useless ability, as it is possible to walk back to the Onions, taking more than four Pikmin as well; in actuality, the pilot is carried back as quickly as if all flowered White Pikmin were holding him, regardless of the colour of the actual Pikmin doing the carrying. The practical application of this is that it saves precious time: additionally, while one Captain is being returned to the landing area, the player can control the other, thereby getting a little extra done.
This ability is similar to that in Pikmin, which is activated by holding down on the D-pad. Up to five Pikmin subsequently carry Olimar away, in doing so rendering him impervious to attacks. If any Pikmin carry Olimar to one of their Onions, the Onion will spin like it is making more Pikmin, but it actually sends out fireworks and Olimar is safely returned to the ground. This function does not exist in Pikmin 2, even though the Pikmin do carry Olimar to the Onion or Research Pod.
If the Captain in the Napsack is picked up by a Dweevil and this beast wanders off the sublevel into the abyss, a glitch occurs.
