Recent reviews by Howling Techie

Even 5 years later, I'm having just as much fun with this game as I was when I first bought it. Part puzzle, simulation, and rhythm game, Oil Blue just feels great to play. The design of the machines have this great feel to them, with each press causing a lovely click, hum, or buzz. Despite the game looking quite dark and gritty, I would say that it's charming.
The gameplay itself lives up to the aesthetics. While it may not look like a lot, even with just three or four machines to manage, things can start to get hectic if you don't keep an eye on things. As I said at the start, once you start to get into the swing of things, it begins to feel like a rhythm game, with you having to manage and the timing for all the machines, while trying to get as much oil as possible without overworking your machines in to disrepair.
One downside I will say is that while the methods of running the machinery is engaging without becoming too predictable, the repair minigames almost feel like an afterthought, with some of them coming down to blind chance, and others being incredibly simple, leading to a weird disparity in difficulty.
A second point I will mention that may not be true for everyone, the system for selling oil doesn't quite hook me in as much as I think it was intended to. Throughout the day the price at which oil can be sold fluctuates through the day, and sometimes there will be special events that can boost, sink, or otherwise cap oil prices, and while I felt like I should be monitoring these prices, strategically selling high, All I did was either sell whenever my storage was full or at the start and end of the days.
However, these are just a few minor complaints for a game that's fun way to spend some time, either having a quick session, or sinking hours at a time in, especially for the price.