It's ok in early levels, but in later stuff it's so jazzed up with filler I can't find any, um, "music" to follow. It's pretty hard to stay on track when there's no discernible melody let alone rhythm.
Other squares should be more like your own: spin faster with proximity, rack up points, get damaged by collision. Also, instead of collision meaning instant death, it should mean loss of points by both sides (particularly the full score of the minimum-scored participant). Then hitting 0 points would mean death (whether for you or an NPC square). Finally, new squares should be spawned by (you) reaching certain rotational velocities, with the requirements increasing geometrically (i.e. reaching threshold x spawns however many boxes are needed to bring total up to y--and holding x means continually maintaining box count y). That way you can more effectively keep NPC count up and also have the possibility of racking up killer combos but at major (though not necessarily lethal) risk.
These changes would add a lot of depth and longer-term playability.
Speed upgrades are a penalty. They only keep your troops spread out and send them to the slaughter before you can take advantage of access to lumber or eliminate trebuchet penalties.
Using a minimap instead of relating in-screen position to overall position would help both issues, but there should also be clear map borders or the play area should wrap around.
There needs to be better feedback relating your position in the full virtual space. It's way too easy to accidentally run to the edge. It also doesn't help having your direction of shooting altered by your own movement due to drifting around the visible screen area.
Using a minimap instead of
Game scales way too slowly. By the time I was allowed to build and use anything cool, I'd long since grown weary of slogging through endlessly tedious levels of no note.
Not only are the levels way to simple and obvious, the whole "screw the nut" premise is also wasted as there's not even consideration of orientation in the solution--nevermind lining the two up and then applying torque to tighten. It's really just "get object A to point B" which hasn't just been done before, but done much better many times before.
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