"Let strength be granted so the world might be mended..."
As a precursor statement, I'll simply state I hate difficult games. While I don't mind a challenge now and then, if a game feels programmed to always win despite the skills on the contrary, I start to get turned off. These can range from a first person shooter with enemy AI having pitch-perfect accuracy or a fighter with opponents a bit too good at countering my moves, games with unfair difficulties can be, no pun intended, a real game breaker. What makes Demon's Souls remarkable is that, unless intentional for whatever bizarre reason, none of your deaths in the game will feel cheap or BS and after your "damnit!" upon your death you'll realize it could've easily have been prevented. While there's the occasional quibble, Demon's Souls will seem a bit too alienating to get completely immersed into the game, but the desire to get better and see more of the game will take over and for a game known for its difficulty, it can also be strangely addicting.
The plot of Demon's Souls is...basic to say the least and serviceable at best. In the kingdom of Boletaria, a great fog has been covering the land with monsters that devour people's souls and leave survivors twisted and violent. Others have attempted to stop the Old One, a great demon awakened underneath the Nexus but they've all been failing, including your character. Awakening within the Nexus, acting as your main hub in the game, it's your job to travel to different environments ranging from a mine, a castle and a creepy dungeon as you slay great bosses, strengthen your character and deal with the Old One.
There isn't really any plot twists, character NPC's don't get much development and there isn't much information that's relayed to you as far as the background of the game's mythos. But what really sells the game is the tone and the atmosphere of the game itself as it's dark, a little melancholy and depressing and at times, I'd even call it creepy. Thanks to the sheer lack of music during regular levels (they appear during bosses, however), traversing levels such as a dark and seemingly abandoned prison with no music can really make the game unsettling. That of course gets pumped up as you taken on the individual bosses which can range from a creature covered in worms and slime to a gigantic knight with a shield at least 40 feet tall or more or a gigantic spider. They hit hard and death means restarting from the beginning so tensions are always high unless you superpower your character in which you can, with the right spells or equipment, have things done in a few minutes.
The controls for the game are very easy to understand as your shoulder buttons govern your left and right handed weapons and shields so while L1 has a block with shield equipped, L2 acts as a parry (with small shields) with possible badass riposte attack or a bash. R1 and R2 are weak and strong attacks with different types of attack for the kind of weapon you have. An example being a weak attack might simply be a normal swing while R2 will create a stabbing attack for a straight sword while an axe will have a big overhead attack. Getting the handle of not only what attacks work best for what enemy but also in certain environments (a sword with a wild swing won't be as effective in narrow corridors as one with a straight jab attack) is key. Wildly swinging and hoping for the best won't yield the best results compared to waiting for an opening and getting a highly damaging strike in. Nearly everything you do costs stamina such as swinging weapons, rolling or an attack hitting your shield so you have to make sure you have enough left to escape harm or you get stunned and open for more attacks. It's easy to get a grasp on how the game controls but a bit of a learning curve is needed on how to best approach a certain situation.
Whenever people bring up games that are difficult, Demon's Souls is often repeated and although attacks can take off a surprising amount of health and you can even be one-shotted, the game is more punishing in that death can come with a heavy price and even further character development can also punish. Upon death, you lose what you've accumulated in souls (XP which acts as currency to buy and repair equipment, way to level up individual stats or upgrading). Once you've died, a bloodstain will be left where you died and if you can make it back there and touch it, you regain your souls but should you re-die before you do so, they're gone for good. And with your items needing to be repaired periodically and stats to get boosted, this could leave you with not enough for anything. This becomes a real balancing act since upgrading any stat raises the price of souls needed to raise it again. So while Strength might cost 1000 souls now, pretty soon any stat upgrade will need 16,000 or more. This makes it a more lengthier progress to get stronger but also requires a specific character build and if you're not a big magic user, there's no point in upgrading it.
One counter balance is that with the aid of blacksmiths and magic trainers, you can beef up your character to be even more effective should you go down a certain upgrade path. Different versions of weapons and bows are available to be made such as Blessed which regenerates HP, Crescent which is the same for MP, Dragon which adds an added fire attack or Moon which adds your Magic stat to your attack. However, farming the stones needed is a major pain in the ass as you need either shards, chunks or pure versions of a certain stone and without a wiki guide, not only can it be tough to figure out which enemy gives what but some pure stones are so rare that you can completely bypass them.
One unique feature of the game is involving the use of its online in that it doesn't have "online" per se. While you can co-op stages and bosses for an easier time, there's some requirements that need to be met first. Since the world is always on so to speak, you can find people in soul form who want to be summoned into your world in hopes that defeating them will also gain their body back and you with an easier boss fight. If not, you can take their advice from messages found on the ground which can range from helpful hints about upcoming traps, where valuable treasures can be found or just weird little comments like "poor guy". A message being recommended will refill that poster's health so it's always beneficial to put very helpful comments. After all, with a game this hard, we're all on the same team so might as well make things easier. What I found at times less helpful are other player's bloodstains which show their final moments before death. Usually they show you someone getting unexpectedly attacked but more often than not for me it's just a guy suicide rolling off a cliff or dying to an enemy you already killed.
Things are not completely flawless in the game as the framerate can occasionally drop, certain components to its gameplay such as how World Tendency works are not explained, the lock-on can be a little flimsy and many deaths came from having the camera not properly looking at what I'm trying very hard to lock on to. And since there's no save points or checkpoints, this isn't the kind of game you should play if you know you're going to be frequently interrupted. But aside from these complaints, Demon's Souls is the kind of game you'd probably abandon if you weren't constantly thinking about it. I wouldn't go as far as to say it's one of the best games ever but it's certainly one with handsome rewards for those brave enough to see what the big deal is.