This is Tim Smith using three ancient Battle Cry boards to replay the battle of Gettysburg with kids between 10 and 17. Tim assigns a General in Chief to each side, has subordinates working underneath them and issues cards in two different ways. The GIC can issue cards to individual Generals or play them himself on behalf of all involved on his side when appropriate (think the Coordinated Attack or Leadership cards), and each General also receives cards individually that are a reflection of his need to react to conditions in the field. Any single unit can only be activated once on an individual turn.
Tim assigns each player a specific role, so they're not playing General Left, Middle or Right. They're Sickles, or Hill, or Reynolds. At one point the Confederate GIC put himself, Lee, in deep peril by moving into the center of a position and having his entire unit stripped from around him. Unlike official Battle Cry rules the win/loss conditions are intentionally muddy, based upon consensus during a post-game-show where everyone discusses who did what things right or wrong. Getting Lee killed off would have been quite a feather in the Union's cap, but as luck would have it he had a Rally card available to him and, as would have happened in a similar situation in history, he was able to pull four infantry units out of the woodwork to come to his aide. The game ended in the waning hours of Day 2 and the Confederates, who looked to be in grave peril at the beginning of the final turn, managed to dig themselves out of trouble and roll the unit count in the other direction.