What are any special effects/methods of killing enemies in Donkey Kong Country Returns?

Solution 1:

You can consecutively jump on enemies. On the third and subsequent bounces, you'll get banana coins. I've read online that when you get to the eighth bounce, you start to get balloons, but I've never gotten that many. A good place to try is level 2-2, Sloppy Sands. After the first checkpoint, look for the squid cannons with a platform above.

Killing multiple enemies with the same barrel will also earn you banana coins in the same way (one coin for each enemy starting with the third). This is trickier to pull off as it requires a barrel and an uninterrupted surface with at least three enemies.

You don't get anything for rolling into multiple enemies. That would be nice, especially on levels like 1-4, Sunset Shore.

Solution 2:

You may already know this, but the method to jumping on multiple enemies is a little different than most platformers. In a Mario game, for example, if you hold down the jump button when you hit an enemy, you'll bounce much higher than if you don't hold the button, and you can just keep the button held down to get the boost on the next enemy too. In DKC:R, you have to push and hold the jump button just before hitting the enemy to get the extra height. The timing is fairly forgiving, but you definitely have to release and re-press the jump button sometime in mid-air, and you have to do this between each bounce to get the bonus from consecutive enemies. Just keeping the jump button held won't cut it. If you don't know this, getting enough bounces to get 1-up balloons is going to be nearly impossible.