Dark Souls 2
Dark Souls 2 is the longest of the Souls trilogy, with the most expansive map and 3 excellent DLC areas added to that. The weapons have increased complexiity and abundance over the first game. at the expense of breaking due to low duability.
Weapons break so often that commoners thought this was a development bug. Turns out you're suppose to be using many different weapons at once. I support this decision as it incentivises trying every new tool that you stumble upon.
Which Dark Souls is your favorite? Start a dialogue in the comments.