Gold Beanie

Mario & Luigi: Partners in Time
Gold Beanies are rare types of Beanies that are found in Mario & Luigi: Superstar Saga. They can be found in Chucklehuck Woods and the Oho Ocean.

Gold Beanies have more powerful attacks than Beanies, and as such net more experience points and coins for Mario and Luigi when defeated. However, they are extremely shy and more often run than attack. The Beanies and Gold Beanies in the Oho Ocean merely float up to the surface, without a need to fight them. Defeating a Gold Beanie will result in a rare badge called the Spike Badge, which allows Mario or Luigi to jump on spiked enemies. (If the Game Boy Horror SP is used, it will yield a Chuckola Badge instead).

Mario & Luigi: Dream Team
Gold Beanies once again reappear as an enemy in Mario & Luigi: Dream Team, now called Golden Beanies. After coming back from Dream's Deep for the second time, the player will encounter a Golden Beanie, escaping from Dreamy Broque Monsieur. The latter will explain that this Golden Beanie is a very rare and powerful enemy that only appears in dreams, and is said to grant legendary loot to whoever can defeat it. A single Golden Beanie may be found in dreams and in a single area afterwards. Gold Beanies are one of the most powerful enemies the player can encounter, but still run away when they can. Defeating one will result in a variety of loot, including more coins and experience points, a DX Bean of a random type, and a rare piece of equipment.

Despite Broque Monsieur mentioning a single Golden Beanie, more may be found after the first one is defeated.

Trivia

 * Interestingly enough, the Golden Beanie drops gear items as small Gifts rather than large Gifts, a rare case of this.
 * The Golden Beanie is the only enemy in Mario & Luigi: Dream Team to drop four different (gear) items, the most any enemy has the potential to drop in the whole Mario & Luigi series.