From the Super Mario Wiki
DKC 3 -- Barrel-Blastapalooza was an online Flash game that was hosted on the now defunct Donkey Kong Country official website, as well as in the Nintendo Arcade section of nintendo.com. It was created to promote the Game Boy Advance release of Donkey Kong Country 3.
The objective is to guide Dixie and Kiddy through a short maze while collecting all DK Coins on the path. The Kongs start out inside a fixed Barrel Cannon and the player must drag and place Barrel Cannons along the way to guide them. They have a supply of ten Barrel Cannons. Upon placing a Barrel Cannon, the player can change its direction using a small cursor next to it. Once the player decides their Barrel Cannon set up is ready, they can press the "FIRE!" button and blast the Kongs through the maze.
A TNT Barrel is displayed on the down-right corner of the screen, with a long, burning fuse serving as a timer. As the barrel approaches its explosion, it starts flashing red; if the fuse burns out completely, the Kongs will be forced to start navigating the maze regardless of the set up. If the Kongs are shot into a wall, the player will lose and be led to a screen allowing them to restart the game. If the Kongs are launched into a barrel they have already been through, they will simply pass through it. If the Kongs reach the finish and collect all DK Coins, the game is won and will redirect the player to a screen which congratulates them. Both the win and game over screen feature a render of Dixie Kong climbing a rope, next to a link to the official Donkey Kong Country site.