Julian Ridden has been presenting on gamification in Moodle all morning at the MountainMoot. I can’t possibly give every single bit of the presentation but one of his later tips in the presentation was using both conditional activities and completion to remove a label (an image or instructions) once a task is marked complete. In other words, rather than unlocking something through completion the opposite occurs: the image or resource or activity disappears.
Pretty cool way to make instructions that are no longer needed in a course disappear once something has been completed.
What it looks like: