There are a number of cards I think have potential, but a lot is going to depend on rotation, potential bans, and how powerful the upcoming three Standard sets of this year will be.
Nasty in aggro, going wide, tokens and more
White 3
Magic Presents: Chocobo Racing events Event Promos and Materials Squall, SeeD Mercenary and Ultima Standard Showdown promo provide one promo to the winner of each weekly Standard Showdown event
However, now that Vein Ripper has basically disappeared following the ban of Sorin, Imperious Bloodlord, Pioneer has become hospitable for Cauldron Familiar strategies again
Thats because it can generate up to four Lore, has Evasive (so it can only be challenged by other Evasive characters) and has decent Strength and Willpower, at 5 for each