Keystones in Path of Exile have a big impact. They always offer significant power, but they also always offer a significant weakness as well, giving players a different style of gameplay to build around and altering the value of other stats. That’s the philosophy laid out in the start of the newest article covering the design of the keystones in the game’s Legion league, explaining how the stones went from concept to finished product for several of the keystones.Check out the full walkthrough to see how these mechanics were refined into their finished forms as well as understanding a bit more of the process of the design. If you missed it before, don’t forget to take a gander at MJ’s hands-on with the league.
Source: Official Site