Nice idea. Could be expanded further.
Nice song. Quite amusing in this context. Graphics work well, though are a bit derivative. (Are they stock buttons?)
Time attack is probably the most obvious mode. Nicely done. Maybe needs a bit more pizazz?
Reflex - another obvious idea. Also nicely done. Though with the time the button animation takes, I think the theoretical top score would be more like 50-60.
Endurance mode was fairly inventive, conceptually, but a bit ridiculous and not much potential for fun, I felt. I actually think it would have been better (not necessarily from a fun-game point of view but from a keeping-the-ridiculous-angle point of view) if the scores were hidden. But that would only really work if the list was longer.
I like the notion of being told you're #xxx in the high score list, but not actually knowing how much higher you'd have to go to go up a place. It'd just add to the whole element of 'stop when you think you've done enough'.
Challenge - my favourite mode. Inventive, with some nice ideas, which took some picking up on, like the 2 shades of red and the upside-down buttons. Maybe it'd have been nice to have had some moving buttons too? Also, I have a feeling a lot of folk may have real trouble with the deep red differentiation, if they're even marginally colour-blind.
I got to 39. I noticed that scores seem to only show for that instance. Strange stuff.
On a related note, it'd be nice to have a personal high-score list, given the circumstances. That holds for all modes.Specially time attack and reflex.
Be nice to have more modes maybe. Challenge mode could perhaps be expanded further. With maybe one 'easy' version, one 'hard' and one 'randomised positions, which ensures the buttons don't overlap but is otherwise randomly positioned.
And maybe a timing game. Pressing the button and trying to get a count-down as close to 0000 as possible?
Other than that, I think you've covered a good variety of game modes.
My only remaining reason for not giving a higher overall is the inherently limited nature of the game.
Stay funky,
- Bez