all your report are belong to us

Read the B&R list announcement at WotC's website (effective September 1, 2017).

• Yawgmoth's Bargain is Unrestricted
• Monastery Mentor is restricted
• Thorn of Amethyst is restricted

Also note the Planeswalker rules change:
Starting with this set, all planeswalkers past, present, and future will have the supertype legendary. They will also be subject to the "legend rule." The "planeswalker uniqueness rule" is going away. What does this mean? In short, everything that's true about legendary permanents will now be true about legendary planeswalkers.

Will this shake up the environment?