My response was more in the spirit of making searches easier to navigate. If you have a general idea of where you might find the information you’re looking for, you can save yourself a bit of time by searching the topic directly, rather than potentially wading through dozens of unrelated posts. If the information about what to put in my Rend build’s fourth cube slot is likely to be anywhere in the forum, it’d probably be in the big Rend guide. Maybe I wasn’t clear enough, but I hope that makes sense 
Assuming I haven’t made a muddle of the links (do I ever wish I was at my PC right now!) I managed to find a few different posts from a few different people talking about possible fourth cube slot items, searching within the Rend guide using the terms ‘fourth cube’, ‘fourth slot’, and ‘season 22’. Some of them have to be read in context of prior/subsequent messages though. Hope that helps.