Dark Souls III is an action-RPG known for its difficult gameplay. You play as an Unkindled undead, trying to bring back the Lords of Cinder.
Pro Can give a great feeling of accomplishment
The Dark Souls series is known for its difficulty and Dark Souls 3 is no exception. It's filled with difficult enemies and tough boss battles, able to cause you grief on more than one occasion. However, every time you progress to the next safe spot or defeat a boss you'll often be filled with a mix of joy and relief. Beating this game will almost certainly feel like an achievement.
Pro Stunning environments
The world of Dark Souls 3 looks amazing, so you may often feel the need to stop and take in the beautiful sights. This can be the sheer size of structures, mountains, or caves. It can also be the decorations, inscriptions, or details in a room. There's always so much to look at, allowing you to truly immerse yourself in its world.
Pro Unpredictable boss battles
The boss battles in Dark Souls 3 consist of several phases, changing up how the bosses fight over the course of the battle. They will gain new abilities, become more aggressive, or reveal various nasty surprises. This creates an enjoyable experience that is different from most modern games where bosses are just glorified pincushions.
Pro Great combat system
Dark Souls 3 is a very fast-paced game but it's not just about having quick reflexes. A lot of the combat comes down to exploiting your enemies. To do that, you have to learn their patterns and attack the moment they pause or perform a telegraphed attack. This creates a combat system, which rewards awareness and patience, and is satisfying to master, even if you don't have extraordinary reflexes.
Pro A great variety of equipment for almost any playstyle
You'll be finding new pieces of equipment quite often, giving you many options to choose from. Each one has its strengths and weaknesses, allowing you to pick the equipment that best suits your playstyle.
For example, heavy armor will make you move slower, but you'll be better protected. Greatswords have a wide reach, but you swing them really slow. Conversely a dagger is very fast but it has a horrible reach.
Con It's hard
You should try avoiding the trap of great review scores since most of them fail to mention the difficulty. It's simply put - hard. A lot of the combat requires quick reflexes, good mechanics, and the mental fortitude to carry on after failing for hours. If you're new to the Souls-like genre or simply want to enjoy a relaxing evening playing a video game, you most likely won't enjoy Dark Souls III.
Con Poor support for mouse+keyboard control
The default DS3 key/button bindings actually prevent full use of certain weapons by requiring the shift key to be pressed and not-pressed simultaneously. Rebinding is possible, but limited by issues like the left mouse button overriding all others and certain bindings not actually working in game (e.g. Shift+MiddleClick).