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Bonus Coins are golden coins that appear in Donkey Kong Country 3: Dixie Kong's Double Trouble! and Donkey Kong Land III. They are the successor to Kremkoins from each game's predecessor, Donkey Kong Country 2: Diddy's Kong Quest and Donkey Kong Land 2. Dixie and Kiddy Kong can obtain a Bonus Coin by completing a Bonus Area. Once they have obtained it, the Kongs cannot obtain another by completing the challenge again, as the Bonus Coin is checked out. The symbol on the Bonus Coin is identical to the one on every Bonus Barrel.
Donkey Kong Country 3: Dixie Kong's Double Trouble!
In Donkey Kong Country 3: Dixie Kong's Double Trouble!, there are a total of 85 Bonus Coins. Each level has two of them to collect, but a few levels in Krematoa have three Bonus Coins, and Rocket Rush has none. The later bosses also relinquish a Bonus Coin when they are defeated.
At Krematoa, each level is obstructed by a boulder. They can only be destroyed if the Kongs visit Boomer and pay him 15 Bonus Coins to demolish the boulder per each of the first four levels. (This concept is somewhat similar to how the Kongs pay a Kremkoin toll to Klubba per accessing a Lost World level each). For the final level, Rocket Rush, Boomer charges a higher fee of 25 Bonus Coins to destroy its associated boulder.
In the Game Boy Advance remake, 13 more Bonus Coins were added, bumping up the total to 98 Bonus Coins. The extra Bonus Coins are obtained from completing Bonus Areas within levels of Pacifica and defeating Kroctopus in Razor Ridge. To accommodate this change, Boomer now charges 18 Bonus Coins per demolishing one of the first four boulders, and 26 to demolish the final boulder blocking Rocket Rush.
There is a way to obtain every Bonus Coin without completing every Bonus Area:
Donkey Kong Land III
Bonus Coins have a different role in Donkey Kong Land III, which features 78 of them in total. Bonus Coins can be used to play the Memory game from Bear's Sheepy Shop in each world. The Bonus Coin fee varies between each world. Oddly, the paid Bonus Coins are not depleted from the player's count.
Collecting every Bonus Coin causes the Time Attack mode to be unlocked.