Volatile Dweevil
Mandarachnia explodus
The Volatile Dweevil is a kind of enemy in the Pikmin 2 game. They resemble walking bomb-rocks except that they are dweevils. Unlike other Dweevils, they will start to detonate as soon as they start walking. They are also known to drop from ceilings. The only way to kill it is to run and wait for it to detonate, although if you are in peril you may use ultra-bitter spray to petrify it and then kill it. You will at least get nectar, or possibly spray.
Olimar's Notes
The Volatile Dweevil is one member of an insect family known for mimicking objects by carrying them on their backs. The dweevil family exhibits a most unusual characteristic whereby the creature's behavioral patterns actually changed based upon the object the creature carries on its back. The Volatile Dweevil has one of the most potent of all the species within the dweevil family, due to the habit of carrying explosive devices. Approach with caution and/or body armor!
Louie's Notes
The scorching species combusts upon contact with the tongue. Only edible by the adventurous and asbestos-tongued.
How to Kill
Pikmin
Throwing Pikmin at it won't have much effect. It will guarantee that the dweevil sets off, but it can't be stunned, and its health won't be depleted faster if attacked. Also, if the Pikmin don't flee fast enough, they will be killed by the explosion, giving another risk.
Captains
Run up to it and punch it once, then run. That way, it'll explode while you're away. If there are other enimies near it, hit it once, let it follow you, and walk in circles around the other enemy. When the Dweevil is about to blow, run away.
2-player battle
In battle mode if the roulette wheel lands on Volatile Dweevil you can drop one on the enemy at any time by pushing Y. Quite possibly the funniest roulette option--set him up and laugh maniacally as your opponent's Pikmin--and your opponent himself--get blown to smithereens. Kablammo!