Novelist Mazarkis Williams spotted a hooded man on four different fantasy covers and is offering a “bounty” for readers who can spot more examples in the bookstore.

Last week, the writer promised “a prize of arguably huge value” to anyone who can find the hooded man lurking on other book covers. He also offered “a prize of immeasurably less value” to any reader who can find five covers reusing another image.

Here’s more from the author: “Who is this masked hooded man? Where will he turn up next? Where else has he been already? Putting to one side the issue of this stock-character-of-easy-virtue I hope that the fact four such varied and fine (though I say it myself) novels lurk behind his menace is a fact that puts fresh shine on the well-worn directive never to judge a book by its cover.”