Because it deletes all the items in a list, it can be used in a wide variety of situations. The dropdown selects the list.
When a pattern is repeated correctly:
. . . if <(played notes::list) = (correct notes::list)> then delete all of [played notes v] generate new sequence::custom . . .
When all enemies are defeated
. . . if <(enemies) = (0)> then delete all of [enemies list v] . . .