To hard in the beginning, but otherwise an fantastic Metroidvania experience
Project Black Sun feels like if Super Metroid, Metal Slug and Flashback had a baby. The overall map design follows closely into the footsteps of Super Metroid, including a large free roamable map, item collections to unlock new areas and boss fights. Where it diverts from modern Metroid games is in it's core combat mechanics, like in Metal Slug the player character will perform a knife attack when close to an enemy and is able to throw grenades. When shooting enemies from a distance the game takes inspiration from Flashback and doesn't allow shooting up, down or diagonally, only shooting straight is possible. Shooting while jumping is also not possible, one has to stand firmly on the ground to be able to shoot. Furthermore the weapon has to be reloaded, which will take a second and leave one open for attacks.
This means that the game requires a much more methodical style of play, as one needs to keep close track of the available ammunition, which is limited, and time the reloads well to when no enemy is near, dodging enemies to evade them or set them up for a knife attack instead of shooting them becomes an important strategy.
Aside from the requirement for a more methodical style of play, the game also comes with an insane difficulty. One starts the game with just two hearts, meaning two hits and it's game over. Ammunition is also quite limited at the beginning, which means the start into the game can be a little rough, even the first savepoint happens to be a little to far of for comfort. Later in the game additional items and actions do make the basic navigation through the map much easier and faster, the insane difficulty is however is still present in the boss fights, which require dozens of retries till one has figured out the pattern. However while one dies a lot in the game, the overall frustration is pretty minimal, as it keeps every collected item even in the case of death and automatically refills the healths and ammunition to full when restarting. It also never takes long to get back to where one was killed and repeating the same passages again gives valuable training in dealing with the enemies and a passage that might have been challenging at first, will seem easy after a few tries. In this aspect the game is quite similar to Demon's Souls.
In terms of presentation the game looks great, with emulating quite successful the style of a real SNES game and having extremely well animated sprites. The music and sound also fits the setting and exploration very well. It simply looks and plays like a well polished SNES game of the past.
The games main weakness for me is the map, while an automap exist, it does not keep track of items, doors or passages, just whole rooms, this makes it impossible to actually figure out where one has to go, as nothing indicates unexplored terrain. The games non-linearity also means that there is no obvious 'right path' to take and frequent back tracking is required. In the end I resorted to drawing myself a map of the game that includes the needed additional information, as it was just to frustrating to walk around in circles trying to find where that one locked door was for which one just collected the key.
There are also a few smaller issue that could be improved up on, the statues at savepoints for example don't give any hint when they are activated, which is confusing till one figures out that they automatically activate when entering the room. There are also a few falling rocks and spikes that are almost impossible to avoid the first time around and that could be better indicated with a few more particle effects.
Another issue with the game is the complete lack of story, which feels a little lazy. The intro, which looks quite nice, just tells a pointless story of some guy who fell down into a mine and has to find it's way back out. It never addresses where one is or whom one has to fight and one doesn't find out anything over the course of the game, as that intro is the only story bit the game provides. There is no story outro, just credits at the end. A Metroidvania game certainly doesn't need long elaborate dialogs, but a clear sense of what is going on would have been nice.
Overall I enjoyed this game immensely, it looks fantastic, provides a good amount of content and simply plays like a classic SNES game. It's easily one of the very best indie games I ever played. The difficulty is a problem for sure and the addition of a Easy or Normal mode would certainly benefit the game, as not everybody wants to fight a boss 30 times before getting close to even having a chance. But it never really bothered me that much, as it was always manageable and never resulted in tedium, it also helps that the game gets easier over time, not harder. It took me around 10 hours to beat the game and while that sounds quite lengthy, a good amount of time was spend dieing and retrying or just getting lost on the map, as the game world itself does not actually feel that big.
The game is available for PC, Mac and Linux, I played the Linux version.