Apparently I was unclear. Players should not be able to complete the level on the first try. However, the level designer should think that SKILLED, ATTENTIVE players will be able to. If the level designer does not, the level is too hard.
Most importantly, if you do not think a skilled, attentive player could beat a level on his or her first try, revise the level. Give players plenty of warning about everything. If you think that a section is so hard that it will require multiple tries to get past, make it easier.
Levels that follow this rule can still be hard, but they will also be fair.
The difficulty level past level 11, while not quite as bad, is still too high. Level 12 would probably be ok if you got rid of the first section (the easier part), and level 13 might be fine once you add midair steering. The bouncing part of level 14 is ok, but it shouldn't require user input on the fourth one. If the first three work fine, the fourth should, too. The initial part of level 15 is fine, but it should stop at the first black floor. Level 16 would probably work fine if you could see farther ahead. The second jump in level 17 is either too hard or the way past isn't obvious enough. Either way, I can't beat it. I haven't gotten far in level 18, either. It looks like it would be ok once the midair control is implemented, though.
I attempted to summarize, as concisely as reasonably possible, the things wrong with level 11, and I still ended up with a wall of text. In short, the level is way too long, way too hard, and not fun. As soon as you have access to your working copy of Flash, break the level up into multiple smaller levels.
The ice section in level 10 is good. Make it longer, and make it impossible to simply roll down the center. The zig-zag section at the beginning is ok but belongs in a separate level. The section at the end should be removed. It doesn't make the level better in any way.
I thought that the stuff mentioned below would be the worst of it. Then I got to level 9. The starting blocks are so high up that you can hardly judge distances, and you can easily see them disappear. The hole in the second platform is nigh invisible, and it's too hard to tell where you should jump at the end. (Tip: remove this level.)
Level 5 is even worse. Going to the right after the third white wall kills you, but you cannot see the gap beforehand. The red stairs aren't long enough to be easily climbed at full speed, and there is a fake exit at the end.
Level four contains the first major mistakes. You cannot see the ball when you reach the first jump, and one of the tubes does not go through (the marking doesn't help).
VicReL28: Yes, it will use your computer memory. That's the point.
That isn't to say that it will use more of your computer's disk space; just the memory. That's why it's so important - if your storage space setting is less than "unlimited," the memory the game can use is also limited.
217 continues on insane, then 0 on easy. It's too bad that I didn't figure out that holding left makes it easier until the bouncy ball level. (Hint: hold left at all times, even when you press right.)
The real pac-man is, apparently, good. This isn't. Here's why: http://www.atariage.com/forums/topic/68707-pac-man-ghost-ai-question/page__st__25__p__1300294&#entry1300294
I'm not sure how to beat the boss with only the sword, but it seems to be necessary; I did everything else without the blaster but did not get the achievement. I tried to hit the boss with the sword, but it didn't do damage.
It's really too bad that people rate good games down due to difficulty, though I'll admit this game was a little too hard. Still, the level design was good (with a few exceptions), and the cannon levels were more fun than either TBA game. Despite its flaws, it is definitely worth a 5.
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