Krarks Other Thumb (and associated dice mechanics) Coin flips have been a part of black-border Magic since the start, but somehow rolling dice never had the same level of legitimacy, and it was pigeonholed as an Un-set mechanic until very recently
The Emerald/Sapphire deck has a lot of cards focused on Big Hero 6 , but Lorcana regulars like Stitch and Goofy get to shine, too
Notable Cards: Reprints and $$ The money cards in this list are Homeward Path, Lightning Greaves, Ruination, its three commanders, Garruk Wildspeaker, and Collective Voyage
In a deck with plenty of kill spells (easy to do thanks to Vren's black mana), you can wind up with an army of not-quite Relentless Rats while your opponents are tearfully pitching their beloved creatures into their graveyards
Everyone knows how good Reclamation Sage is, so tacking on vigilance and an extra, optional ability makes for a stronger card
Damage prevention effects can be useful with goad and other forced-attack mechanics like the one on Bident of Thassa