I'll have to give Success credit were credit is due. It's refreshing to see a company try new techniques and do a good job of presenting it. Essentially you're a witch on a quest to grab "willows." Apparently, they're delicious.
Unbeknownst to her is that she is actually on a quest to help some fairies get rid of the mist that is blanketing the world. I guess they're a little bit miffed about not seeing the sun for a few months.
Cotton is a good shmup and will give you plenty of challenge. You have the help of a fairy (or fairies if you pick more of them up) that acts like an option. You can charge your shots to use magic. You can also charge your fairy or charge both buttons for some impressive magic attacks. To collect magic you have to shoot down certain enemies that drop crystals. You can change the crystals to four different colors. Two will give you magic (up to four can be held at any time) and the other two give you experience points for your weapon. I believe this is the earliest attempt, that I know of, that you can power up your weapon using experience points. So, you have a lot of weapons at your disposal. The trick is, of course, when to use your shots, bombs and magic and the combination of the three.
This shmup throws everything at you. What hampers you down a bit is the size of the hitbox on the character: it's huge. This is especially cumbersome when the game bogs down with enemies and projectiles. Needless to say there is some slowdown. Also, this game is hard, like original R-type hard. It's difficultly is what loses it a point. You have completely memorize levels to stand a chance and it does not help that you lose half your weapon's experience level when you die.
Bottom-line: A good, solid shooter with new techniques, whimsical storyline and great music. Its difficulty might be a turnoff for some. Definitely challenging and at times frustrating. It's also one of hardest to get ahold of (like over $100). It's sequel for the Sega Saturn is a much more balanced shmup at less than half the price.