Segmented Crawbster

The Segmented Crawbster is a boss in Pikmin 2. It is the boss of the Cavern of Chaos' final sublevel (10), which is located in the Wistful Wild. This is the only place where it can be found. This crab-like creature has one large arm, and an exceedingly smaller left arm. It also has a rather thick shell protecting it. This creature rolls after the active leader, occasionally crushing Pikmin with its hard shell. If it crashes into a wall, it can cause boulders to fall. It will then struggle to get back up in an upright position, and while doing so will expose its weak spot: its flashing underbelly. Eventually, it will then get back up and swing its large arm around back and forth two or so times, causing buds and flowers to wither, and continue its assault.

Strategy
In order to defeat this creature, it must be lead into a wall while it is rolling. Its rolling is more focused on the active leader, not the Pikmin. There is a slight chance that eggs will drop along with the boulders; these may contain Mitites, sprays, or nectar, and they will usually continue to drop every time the Segmented Crawbster crashes into the walls. After the boulders have fallen, the leader needs to be on either the left or right side of the creature and must throw his Pikmin onto its underside. After enough time has passed, it will get up and swing its bulking arm, which can't kill Pikmin, but does knock off their flowers. Once defeated, the Segmented Crawbster will groan and squeal as it is underbelly explodes violently, spewing goo particles all over the immediate vicinity, before dropping the Silencer.

In terms of which Pikmin are the most effective for defeating the Crawbster, it is advisable to use a group of around 10-15 Purple Pikmin – they must have flowers so they do not lag behind and get crushed. Care must be taken if one is to use them, as if they have lost their flowers due to the arm attack, they will surely be crushed by the roll. However, if few/no Purples are flowers, flower or budded Red Pikmin can do the job, as they have average speed and the second strongest power in the game. A group of 15-25 Red Pikmin is a good number to attack the Crawbster with.

For a speedy completion, the player can dismiss 100 Pikmin near its backside right after it falls from the sky, and then get ready lure it into a wall, away from the Pikmin. Once it hits the wall, the Pikmin that were chasing after it should start attacking at a steady pace.
 * Using ultra-spicy spray is advisable since it makes the Pikmin very fast, making it easier to avoid the rolling, especially for Purple Pikmin. The spray effect lasts for about two assaults.
 * Ultra-bitter spray can also be used to delay the end of the Pikmin's attacking time.
 * The falling rocks land near the active leader, so leaving a leader outside the arena and switching to them whenever it hits a wall is a good tactic.
 * Another good way to avoid the falling rocks would be to zoom out the camera as far as it can go (with ), and change the view to top view mode (with ) before the battle. This will give you an extensive view of where each rock will fall, making it easier to avoid them.
 * When attacking the Crawbster, be sure to throw Pikmin from the creature's left side (your right). This will minimize the amount of Pikmin struck by the Crawbster's bulking arm, and in turn, keep your Pikmin at flower level.

Trivia

 * The Segmented Crawbster cannot be brought to use its rolling attack in the Piklopedia, for it only chases after leaders.
 * When it crashes into a wall, it may cause some embed glitches to occur.
 * When it falls down on the tiled floor in the sublevel where it is found, pieces of tile will fling from the impact; however, even in the Piklopedia, where no tiles are found, it will still show tiles flinging from its fall, as they are a part of its impact animation.
 * The Segmented Crawbster is the only regular boss to not be found in the Pikmin 2 Challenge Mode. It is also the only boss that Louie cannot be seen with.