From Pikipedia, the Pikmin wiki
The Unspeakable Wonder (トレジャー・オブ・ワンダー?, lit.: "Treasure of Wonder") is a treasure in Pikmin 2. It is a golden crown which closely resembles that of Princess Peach from the Super Mario series. It is found on top of a snowman's head in the Valley of Repose, near the Frontier Cavern.
Collecting the treasure
After clearing a path, be wary of the Armored Cannon Beetle Larva buried near the treasure. This beast has the vantage of location, so it can be difficult to attack. Try to have it release a rock down one side of the slope, then run up the other side quickly with Pikmin and throw them onto its body; when they are flung off, whistle them back up. This strategy should mean that the Cannon Beetle does not turn around, as long as Pikmin are quickly thrown back on.
Because of its position, the treasure itself can be difficult to get Pikmin to carry. They often cannot reach the ground while holding it, and take a long time to maneuver into a suitable position. The best approach is to throw Pikmin at all sides of the crown. Yellow Pikmin are recommended for this, as the treasure is somewhat high. Purple Pikmin are also viable, as only 4 purple Pikmin could easily take it down.
“What...is...this?! I've encountered countless treasures on this expedition, but I've never seen anything like this. All I can say about it is that it's both astounding and absurd.”
“Amazing? More than amazing! It is so overwhelming that my CPU is acting oooooo... Brzzkpt! Beeep! Zzzorrrt! Krzzbaaaaah... ... Rebooting... What a spectacular find!”
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