Zakuza, The Ruin Tyrant

It is a finisher. Charge means the 4 damage lands the turn you play it, and the ability adds 1 damage for each of two other entities that attack the leader that turn. Zakuza doesn’t give itself Bloodlust, so the turn it arrives is worth 6 extra damage at most: its own 4 and +1 on two allies.

Use the ability before you attack, on entities that haven’t attacked yet and don’t already have Bloodlust. Unbound Striker and Flashfire Duelist are the natural targets because both have Charge. Zakuza plus the Duelist from hand is 9 IKZ, so that turn can come from an empty board; Zakuza plus the Striker from hand is 11, so portal the Striker from your Alley instead.

Under Scarlett, Zakuza and two empowered allies are three separate combat hits on the leader, more than the two her ability needs.

With Sanguine Gate, portaling Zakuza gives an entity with Bloodlust in your Garden +3 attack, its Gate Power, and Charge lets Zakuza attack the same turn. The Gate checks for Bloodlust as it resolves, so have a Bloodlust entity like Steel Talon in the Garden before you portal.

Seven IKZ leaves little else that turn. Hold it until the damage it adds finishes the game, not as a 4/4 on curve.