a black perl in an oyster - birth of Venus and the Tiphoons - the sperm of a dead father - etc.
In Graphic dessign they use to do a BrainStorming - just like a thread where people propose ideas.
To do a brainstorming, people should put some words as a title, perhaps inside some [ ]. Then someone collects them and obtains another word resulting from merging a sequential pair of them. Finally, a certain monster should emerge from these mergings. The previous 'corpus' of words might help in building the context of the resulting image. It is some sort of funny working.
The most difficult part is finding a graphical symbol for this image. It should support different formats and sizes. Study where it should be needed and how it should be displayed.
Finally, some finished proposals should be submitted for everybody to vote for the most attractive one.