Most of these are on the maybeboard already: Winding Constrictor - Have it. As you said, it messes up Persist, and might cause a combo piece to die, as its ability isn't optional. Vizier of Remedies - Have it, and it's due to go in Combo. It can negate the Persist cost which is all I need. Hapatra - Have this one too. Can combo for infinite creatures. Sun Titan - Have one, awesome utility. Might find a place. Spike Weaver - Hadn't seen this card before. Potentially useful utility. Vish Kal - Have it. High CMC, but it can sac as an instant and combo destroy creatures, so it might find a place. Requiem Angel - Don't have it. Combo potential, but high CMC.