The creature card you return, if any, isn't a target of Black Sun's Twilight
The most important questions on how "economical" it is to play Magic: the Gathering Arena remains unknown: how much time or money does it take to earn a tier-one Standard deck or to Draft.
IV seems to give this card a little more oomph than Chandra, the Firebrand did, and Im pretty sure bloodrushing a Ghor-Clan Rampager on a Phoenix is one of the dictionary definitions of a BIG GAME (TM)
I kept building though
You can stick with Edgar Markov and build an aggressive Vampire deck by adding more lords, Shared Animosity, and other aggressive tribal-matters cards, or you can go with Licia, Sanguine Tribune and build lifegain combo with Sanguine Bond, Exquisite Blood, Defiant Bloodlord, and the like
For most Cubes though, I love Walking Ballista as a solid card that can go in any deck that offers relevant support to artifact decks and stuff like delirium