Nevermind - I missed the For Each (Ordered) and was doing just For Each.
But just for people who are unfamiliar with Construct 2, I figured I'd at least post the exact code:
System Event (For Each (ordered) <yourspritename> Order by <yourspritename>.Y, descending.
Sprite Event (compare Y) if Sprite.Y < Player.Y
Sprite Event Is on Screen
Action Sprite Event Move to top layer
Hope that helps anyone else that was confused.