Sandworm

The Sandworm is a boss that appeared in the game Pikmin:The After Years. It resides in two caves, the Carnivorous Cave and Rememberance Ravine. It is a giant beige worm and is about twice the size of the Emperor Bulblax from Pikmin 1. It has blood-tinted teeth and glaring red eyes. The Sandworm likes to eat other creatures, especially the Coconut Jellyfloat.

Attacks
When you first encounter the beast, The Ship will warn you that this beast goes for BLOOD! Since Pikmin don't have blood, the Sandworm will go after the current captain. It will occasionally burrow back in the ground. Once it does this, be careful, for it will jump out of the ground and lunge for you. The farther away you are from when the boss appears, the easier it is to avoid this attack. The only way to damage this boss is by hitting its tongue.

How to Kill
Try tricking this monster into eating a Bomb-Rock. Fortunately, there are many bomb-rocks on the ground when fighting this creature. It will fall to the ground, dazed, with its tongue sticking out. Chuck Pikmin, preferably purples on its tongue. Once it regains consciousness, it will stick its tongue back in its mouth and any Pikmin still on it will be eaten. Repeat the process and it will explode in a gruesome manner, leaving only its head to be carried back.

Trivia

 * This boss battle has a similar strategy to that of the Emperor Bulblax in Pikmin 1.
 * This boss battle is similar to that of Molgera as they are both worms and their weak points are their tongues.
 * This boss is also based on the creatures called Sandworms from the movie Dunes.
 * In Pikmin 4 (Wii U), it is only mentioned for Olimar's notes in the Acidic Drenchworm.

-- Gamefreak75

In Pikmin 3: The Progg Wars
The Sandworm is a boss, looking much like its After Years version. It shoots nectar to try to encase your pikmin in jello. After that it will get more nectar from nearby flowers. If you destroy the flowers,It will have no fuel(Its a robot in this game)and die.