Diamond Long Legs

The Diamond Long Legs is a mini-boss encountered in Pikmin 4 (Wii U). It is the rarest arachnorb in the game, only appearing once in Silver Lake. It also appears in 2 caves, Chaotic Cove and Spider's Web. It is located in a snowy arena to the east of the landing site. There are gems that are arranged into a shape of a web. Rock Pikmin are recommended. It has a covering made of diamond, which is why rock pikmin are advised. When defeated, it drops the Snow Parka upgrade.

''This species of arachnorb uses gems or hard minerals as a defense mechanism. It uses the minerals as armor to protect itself from enemies. When it's armor is removed, it is vulnerable to attacks. Recent studies have also shown it has the ability to "regrow" it's diamond covering. But it takes a lot of time, which is why it must be defeated as soon as possible when its squishy core is exposed.''

Strategy
Rock pikmin are probably your best choice for this boss. Their immunity to being crushed and penetrated makes them the perfect type of pikmin. If you don't have rock pikmin yet, or you just don't have them in your squad, it's best to just leave it alone. It can be a tough battle without the rock pikmin. With them, however, it is one of the easiest bosses in the game. Keep in mind that it can "regrow" its armor. Once you expose its squishy abdomen, quickly defeat it before its armor comes back.

Pikmin 10
In this game, the Diamond Long Legs is a bit more common. It will be pretty slow, going as fast as the Raging Long Legs not raging. Using Rock Pikmin to break the main diamond(50 direct hits) you can now attack its body. Be aware that it will go faster now, just slightly faster than Beady Long Legs. Breaking the crystal covering its joints(10 direct hits) will make it lose a quarter of its health. When killed, it will roar, stiffen up, and it's body will shatter like crystal, as well as any not destroyed joints shattering as well.