ARRG, FUCK THIS GAME!
Sorry about that. You deserve better than no stars, but I don't even care right now, the frustration I've built up needs to be vented.
A hard game demands the player to cope with a lot of gameplay elements in a short amount of time, but when that rider that chases you gets thrown and you've got to use your boost, it becomes damn near impossible.
I played the level where you get chased by a horsemen for FIVE HOURS straight and could not get through it. The best I did was throw off two riders, but that only happened three times out of the hundreds of times I tried that level. Most of the time I wouldn't even throw the first rider off before dying.
Hard is good, but UNFAIR is rage inducing. It's a rare occasion when you get into the zone and you're playing near perfectly, but then suddenly, the game's random obstacle generator throws a volley of arrows at you, which you block, only to run face first into a tree branch while in the middle of your shield lowering animation, even though you're mashing the duck button. That's just absolute bullshit. It's a scenario where your failure is guaranteed through no fault of your own. The parameters need to be tweaked so that that scenario doesn't happen.
That or the recovery animations need to be interruptible or shortened, because at that high of a speed, the controls feel much too unresponsive and slow.
When you're not in the zone, the issue of time becomes the game's biggest weakness. At the high speeds of the boost, the camera should zoom out to let you see further ahead. Or the window width needs to be increased to give you more time to react. Or the obstacles need to stand out much more from the background, since their colors and art style makes them blend right in, introducing hesitation in the player's decision making, since he needs to spend time decoding what the heck it is he's looking at, especially with the tree branches and rocks and the other obstacles with no audio cues.
Which brings me to the audio cues: they're terrible. The game is practically impossible without them, but they're needlessly overcomplicated. All the enemies sound identical, especially the horseman that charges at you and the farmer, those two sound pretty much the same, which is quite unfortunate since you can't respond to them in the same way. Either give each unit a distinctive voice that the player can immediately make out, or give each unit one line that they say, so that the player can distinguish them that way. You might complain that the game will be too repetitive, but trust me, by the 300th playthrough, the 2 extra lines you coded for each enemy don't make a bit of difference.