(Update: While the SlimeMech is very difficult and can serve as a brick wall to some players, the shoes I discuss are actually completely optional, along with other optional challenges in the game. So a big part of my review is actually not that big of an issue. However, if you want the achievements, then you will have a big problem.)
Is the game good? Yes.
Now I'm gonna tell you the reason why I hate it, because I'm bitter as hell and it's payback time.
Remember that episode of AVGN where he said "The game needs an expert setting. So they programmed it, but forgot to put it in the menus." That applies here. Severely.
The game is fantastically solid with a good story, power ups to find, great music, crisp graphics, and FOR THE MOST PART a healthy challenge. The problem is that the game has these extreme spikes in difficulty that can bring your fun and enjoyable experience to a screeching halt, leaving you cursing and screaming at the game for making you feel like a punk b**ch.
The SlimeMech boss was my first brick wall. The fight is bullet hell levels of difficult and it took me quite some time to overcome it. The second brick wall came shortly after, when I reached what I believe are double jump boots behind a locked door. My mood upon discovering these boots was ecstatic. My mood after going through over 100 lives trying to get to them was irritated and upset. You have to traverse a gauntlet that spans multiple screens without a checkpoint in between to reach the boots. The first time I reached the third screen and saw that there was no checkpoint (after half an hour of trying), I couldn't believe it. And when I died (naturally), I turned the game off and started the review.
You think this is reasonable difficulty and that I'm just b**ching and moaning? Let me describe it for you. You have to go down a pit with spikes on the walls using platforms that damage and kick you off if you don't shoot them first, avoiding turrets that fire spread shots and mines that explode if you touch or shoot them, ending with a tricky jump that has to be made at the bottom or else you fall in acid and die.
Next room, you have to jump across pits of acid onto platforms that disappear 2 seconds after jumping on them with Super Mario Bros. fire sticks spinning on them that knock you back into the acid if they hit you.
Okay. Okay. I'm done ranting. To finish off, Rex Rocket is without a doubt a hidden gem and criminally underlooked game on Steam. I love it for being so good, but I hate it for halting my experience with these unreasonably difficult portions. It's worth a purchase as long as you're prepared for a challenge.
Now if you'll excuse me, I still need to get those damn shoes.