While this game may not be the best for everybody, here is my opinion on it. The reason i have it now is because i have a non-steam version too and it would be a great comparison to what has changed ever since, which makes this a real classic for me. The reason i recommend it is the very unique gameplay, which i haven't found other games to have. In this review, i'm going to talk about some important things i see in the game.
Starting off, we have the graphics and visuals which don't look very modern, though im not expecting much from a now 8 year old game (since it released in 2010 or so). Unfortunately, the steam version of the game is looking worse than the non-steam variant. To name a few examples, there are grey/missing textures, overly used weather effects and the reflections are worse in general. Sounds are okay, the music is a bit boring, but the crash sounds are very loud. When the vehicles glitch out they might even give you a shock, after a repeating crash sound loudly plays. While all this, the game runs smoothly on 60FPS with no drops on my computer. The graphics are average, but then again the game is old.
On the topic of gameplay, it really is very unique with each map posing a new challenge. I really enjoy stuff like blasting holes in the ground, excavation stages and drilling the tunnels. The TBM is also hungry for concrete and fuel, which poses another need for gameplay. Gameplay itself hasn't changed since the non-steam release, though the physics were better in that version. Normally, the game has 3 stages. First, a detonation stage where you place charges in the ground. After that, an excavation stage comes where you lift the loose rocks out with the front loader into a dump truck and dispose them in a pit. On the harder levels, there are multiple excavation and detonation stages. At last, you get to the drilling part where you control the Tunnel Bore Machine or just TBM in short. You need to constantly fill the TBM with resources, for example concrete plates and fuel in later levels. Concrete has to be loaded onto a train manually, you also have to manually refill should it run out. Fuel is transported on trains automatically, but all trains are launched manually. You also have to control the TBM on the correct course, while keeping everything working with the utility van, should a train derail or a conveyor belt jam. Your TBM also has a drill head, which has to be constantly checked for wear and be repaired if necessary. You also have a fire safety van, which is supposed to extinguish fires and seal water leaks in the tunnel on the harder difficulties. The vehicles can also take damage, which some people might find oversensitive and i do agree on that part. I would certainly recommend the game on this part. Gameplay has two major issues though. One is that the vehicles and overall gameplay is relatively slow, the vehicles barely have any top speed or acceleration. The handling is sensitive, and they can flip over easily at high speeds. The TBM also takes hours to finish sections, though the game can be sped up in multiple ways. The second issue is all the bugs and glitches that are very common in this game.
One thing that is really unfortunate with this game is that it's plagued by bugs all the time. Random crashes tend to happen, and some crashes have some consistency in them. Vehicles tend to fly out of the map, cameras are floating away and game freezes do happen and it's just very messy in this part. The bugs and issues unfortunately make some levels impossible to beat. As said, some glitches have consistency in them, while others have been fixed in the steam release. The flying vehicles issue has been consistent ever since the original release, possibly due to the broken physics in this game. Trying to fully load larger trains crash the game for no reason, and loading levels also tend to crash. The most annoying bug i faced in the original release was that tunnels would be sealed off after reloading the game, though that has been fixed in the new release. The third level was also impossible to beat due to the camera in the TBM floating away slowly, making it impossible to see. The consistent crashes do make it sometimes impossible to play the game at all.
The current release has some issues which do make levels literally impossible to beat. I don't know why they happen, neither do i know how to fix them. There are two "impossible" levels i found. One is the third level "Berlin Subway". Gameplay starts out normal, but the impossible part is the drilling whereas once the drill gets to 83%, the head will constantly and repeatedly jam for no reason. Repairing the drill parts is the only solution, but after repairing them in perfect condition constantly, after a while it won't unjam and you will be stuck forever. The second unbeatable level would be the last and fifth level "Bering Straight". You don't face issues during the excavation stages, until you get to the last and third excavation stage. I have attempted to finish the third excavation stage at 95%, but once the last rock falls into the pit, the 4th detonation stage crashes instantly making it impossible to continue.
My overall opinion is that the game is fun to some point, but it can become boring or even frustrating when the issues start setting in. It may be worth it's price, and again this is only my opinion on the game so take it as you like.
