Probably played this one the most, timing based stuff is great for a mini game. One suggestion would be that it doesn't start the timer immediately, because first play, by the time I realized what was expected of me, some seconds have passed :D  But you do get what you need to do rather quickly, I just wish the game gave me a few seconds to get my bearings :)  Maybe the timer starts the first time you click a button.

Second suggestion, in addition to the crit feedback you got, that the position is changed a bit each "round". Right now (I think) it's always in the same place, just the range gets smaller, would be nice to move it around so you can't get used to the location. I think other games with similar mechanic also use that.

Nice sounds! I couldn't get a crit, not sure if there is a bonus if I get the swing right on the line, but I think that would be cool if not already in there. I didn't notice that the box was getting smaller and smaller until I played for a while! Cool mechanic! I would have loved to use the space bar or a key for max button mashing, my finger was getting a bit tired on the LMB XD. A great play!