There are cards in Battle for Baldur's Gate that designate a player as "taking the initiative", which reuses the dungeon mechanic from the Adventures in the Forgotten Realms set, putting the player in a dungeon called the Undercity, allowing them to gain benefits from maintaining the initiative
Sultai Charm
This works out quite well, as Elminster's +2 allows you top draw a card and scry two, reliably allowing access to this cost reduction
If your opponent can't block flying creatures and ends up taking the damage, you get to take an extra turn
Once you start sacrificing creatures with elite enters-the-battlefield triggers, like Agent of Treachery, you can generate tons of value as they reenter the battlefield repeatedly
Should all else fail, you can go nuclear and hit the Demonic Consultation and Thassa's Oracle combo