It's time for one heck of a big update bulletin coming to you live (but not, like, literally live, because I'm writing this four weeks ahead of time) from somewhere in the middle of the Wilds. They wouldn't let me into Castle Vantress. I'll just have to find some new friends out here.
Commander (2019 Edition) had a larger rules update than usual for an ancillary product, and Throne of Eldraine is no slouch itself for the number of updates. Please do remember that due to the length, I'm going to have to be a little briefer than usual to keep my word count under five digits.
As usual, you'll be able to find the Comprehensive Rules here on our website and Oracle text updated in Gatherer—at this time, one or both of those might not be updated just yet, so I'm describing a general truth here. Keep in mind that this article was written before the rules changes were finalized in editing, so there may be minor deviations from what I describe below.