Kolibri is by the same people that brought us Ecco the Dolphin, so you know off the bat that you are in for a unique, artsy experience. It also has the distinction of being the only horizontal 2-D shooter on the 32X, luckily for us it is actually worth playing.
You don't normally talk about an atmosphere, usually the game is so intense that the graphics and sound mean very little -- this is not so in Kolibri; you can not help but to stop and look at the graphics every once in a while The Graphics are fantastic. The backgrounds are great; beautiful mountains, streams, trees, and flowers really add to the sensation that your character is part of nature. Not only are the Background beautiful, they are also quite varied; you aren't stuck staring at one beautiful rendered tree over and over again. The enemies are various insects and reptiles, and though that isn't a very exciting idea on paper, the developers took the time to make the enemies as or even more gorgeous than Kolibri his/her self.
The sound isn't spectacular, but everything is extremely atmospheric. The background music isn't the techno/rock you normally hear in shooters, it's a soft peaceful beat that never grates on your nerves, only soothes them. Your humming bird's wings hum when you move and so do many of your enemies. It puts you in the mood for the experience far better than you would expect from a game of the late 16-bit era.
The game play is a mix of classic side-scrolling and "puzzles". The puzzle are a nice break of pace, they have you hunting down flowers to destroy the evil bees that are keeping the humming birds away. You are granted the classic assortment of weapons, there is a semi-big problem with the weapons system though, if you accidentally go over a weapon pick up you automatically lose your prior weapon, no matter how powered up you are! This frequently leaves you almost completely helpless against the onslaught of bees you're frequently faced with. The game chooses to not use any Health bars or anything like that, nothing obstructs your game play. This leads to another problem, the only way to know how much health you have is by taking damage or going over a health pick-up.
With all its beauty, the game isn't all that challenging. You have unlimited lives and can take up to four hits. Not only is your bird a tough little bugger, there is health and shields everywhere. Also a majority of the weapons are homing, so isn't really hard to kill your slow moving enemies.
Even though it's easy and some times slow paced, I can see the hardcore shooter fans enjoying this, not as much as Thunder Force 3, but enjoying it nonetheless. I also see anyone who enjoys classic games playing through this title. This game puts almost every thing else on the 32X to shame; it is almost the only unique experience on the entire system and one of the only games on the system where the developer even gave full effort to the doomed out of the gate system.