So write about Gaius' strangely modern medical practices, or about his fondness for disgusting potions and leeches. How did he end up as a physician in the first place?
Or write about how dreadful a patient Arthur is, whether he is injured or sick (or hungover) and how he tests his healer's patience... Who turns up to try and make Merlin feel better when he has a cold?
Perhaps characters have less physical wounds that need to be healed, or maybe it is the kingdom of Camelot itself that needs healing.
And while we're on the subject, don't forget about the wondrous healing power of luuurve!
The challenge will run until 22.00 GMT on 16 November 09.