Unlike Master of Ceremonies, which interacts with "voting", Mangara, the Diplomat first checks if your opponent is attacking you and/or planeswalkers you control with two or more creatures
As long as there is a creature in a graveyard that you would like to copy, getting to exile everybody elses graveyard at the same time is a wonderful upside
A lot of players start with a few staples or upgrades, then come back for the full list once the deck feels right
UnStable used watermarks as a new and improved version of that mechanic, neatly associating any diverse group of cards with minimal awkward templating or visual clutter
It can kill almost any Planeswalker and most creatures, except for maybe the best blue card, Murktide Regent
If you can get a copy of Unpredictable Cyclone on the battlefield and cycle Street Wraith, the results are anything but unpredictable: you'll end up with an Emrakul, the Aeons Torn (which you get to cast, giving you an extra turn!) 100% of the time