DarkSouls is a classic among classics. I really think that the best one of them all is right here. The linearity is perfect, and the difficulty it true. I have played all the souls games off and on and beat them in some shape or form but DarkSouls is the only one I have beaten every which way correctly, understood all the lore, and actively tried to enjoy. It was during a dark and rough time when I was confused & I think it helped me through that dark time. I recommend it, buy it, suffer, enjoy, and become addicted to the cycle. Just remember to check for illusory walls :)