This game reminds me of previous titles of developers - The Lord Of The Rings games. Demon Stone shares many similarities. You go through levels with three characters and you can choose which one you want to control. If you die, you start from nearest checkpoint. You can save only after finishing the level. You also buy new equipment and new skills (nothing crazy, mostly stronger version of already known attacks, new moves are scarce).
However, instead of the LOTR settings and characters you get three archetypes - warrior, mage and rogue - on the pretty basic quest of slashing enemies and stopping the main bad guys. Another feature that is missing is coop. Why they didn't include coop is a mystery to me. To have an option for a friend to take control of another character and help you would be a welcome addition. And it would perhaps decrease some of the frustration.
This is the PC port of originally console game. It shows especially when you try to play the game with mouse and keyboard. It's not an enjoyable experience.
Another problem is camera. The camera doesn't point in direction your character faces, it shows you view from side. Sometimes it's hard to see the enemies. And good luck when you're surrounded by large group of foes who attack from every side. It definitely adds to frustration.
The game can be sometimes really tough and not for the right reason. Like when you need to take down ranged enemies with your mage, but your attacks are always interrupted because none of the companions will come to help you with melee fighters.
I would be lying if I said I didn't have any fun with the game. There are boss battles with a dragon and a giant spider and others. For short sections you take control of a golem or a badass elf fighter with two swords. It's satisfying to clear large amount of enemies with upgraded special moves.
It's not a perfect game. It has many flaws and some parts can be pretty frustrating. It doesn't mean it can't offer some satisfaction.