We're all familiar with the use of wipeouts to completely block out anything that is behind it based on its draw order, however, apparently you can also give it a translucency such that it it only partially obscures the items behind it. I happened upon it earlier this week. I'm not quite sure what to do with it yet but I thought I'd share it with others.
I suppose one could place it within a block behind its contents, set the translucency to 50, and it would '50% screen' existing items behind where the block of new items was place. One could add it to an area of a drawing, set a translucency, then set the draw order of items to be above or below it to screen those items, but only when they crossed into that partial wipeout area.