Mechanically speaking, BK is very similar (if not identical) to the first game's single button, physics-based balloon gameplay, with the A button used to add velocity to the kid. Structurally, however, things change dramatically, with levels scrolling from right to left a la "Balloon Trip" mode from the first game, while balloons are collected in static succession along the way.
Rather than leaving the B button alone, however, the BK allows you to release your balloons and take off on foot, attempting to platform through the level. It's ... difficult. Like, really difficult. It is, however, a realistic option should you lose both of your balloons to the various enemies in your path.
Warp zones, with gameplay styled after BF's balloon collecting bonus levels, are strewn throughout each level, offering a chance to snag some extra 1UPs and points, as well as offering a reprieve from the endless onslaught of anti-balloon animalia.
At $2.99, it's hard not to suggest Balloon Kid to fans of the franchise, but it could be a harder sell to other 3DS owners -- especially those who already received a free copy of Balloon Fight via Nintendo's early adopter Ambassador Program. If you're anything like me, though, you'll want even more totally sweet balloon-on-balloon action via Balloon Kid.
Also, hey, like the original, the music for this one is totally kickin'. It's probably worth your purchase alone, actually. Boom.
Balloon Kid is available on the Nintendo 3DS eShop for $2.99. We're always looking for new distractions. Want to submit your game for Portabliss consideration? You can reach us at portabliss aat joystiq dawt com.