Leader/Follower (pietroglyph's is probably best), Cam/Follower, Sender/Receiver, Drive/Pulley (?), Reference/Replica, Model/Instance, Broker/Agent, Supervisor/W

Leader/Follower (pietroglyph's is probably best), Cam/Follower, Sender/Receiver, Drive/Pulley (?), Reference/Replica, Model/Instance, Broker/Agent, Supervisor/Worker, maybe even Coordinator/Helper (these are a bit long), Lead/Rhythm, Lead/Understudy, Boss/Worker Also good but maybe weird: Alpha/Beta, Red/Black (and if we need 3+, I think Hearts/Spades/Clubs[/Diamonds[/Jokers..]] is fine if you write down the object of the game, so to speak) Slightly humorous but not best: Hivemind/Drone, Hypnotoad/Zombie, Sauron/Saruman, Don/Capo, Drummer/Dancer