This drill works outfielders throwing runners out at home.
Coach will hit bloopers, line drives and grounders right at outfielders and in between them.
It also is a base running drill as runners have to judge whether the ball will drop and then execute a good base running maneuver to score from 2nd.
Early in the season I run it as a conditioning drill and instruct runners to try and score on all balls that drop. Later, I introduce a 3rd base coach who will sometimes hold the runner.