I've been trying to upgrade weapons/gear and am just starting to understand the failstack system and use of different stones for upgrading. I have a bunch of Caphras stones (60 or so) but when I go to the caphras enhacement screen none of my weapons (highest I have is a duo) seem able to be enhanced this way. In reading the Reddit chat about caphras, I ran across someone talking about "RS." So, this is the noobiest of noob questions I'm sure, but what is RS? I'm new to this type of gaming in general and, while I figured out DP/AP, I haven't found any answer to what RS is.