The instant speed of Unravel the Aether is quite good against the likes of Azorius Control, as they rely on either Detention Sphere or Cast Out to deal with your planeswalkers, and unlocking them for cheap is a big deal
Kefka, Court Mage // Kefka, Ruler of Ruin I just wrote a deck around this Grixis leader you can find here - ( This five-drop 4/5 transforming body has an attack trigger to make everyone discard - you too, but no worries since you'll draw equal to the number of card types discarded
Griselbrand Looking for a massive creature to cheat into play
Chaos Wrap Chaos Wrap is amusingly broken
Marang River ProwlerMarang River Prowler in multiples will provide consistent pressure on opponent's life totals, especially if you end up with any kind of boost to their power
These are particularly good in 5-Color Legends, since theyre essentially free to cast with Relic out