<Snipped quote by ArenaSnow>
Is there a rule against using an image that isn't one you made or paid for? Is it fine so long as you credit the original artist/wherever it came from?
I hope that it works the same way as any other CS does on this site, the implicit idea that unless stated otherwise, you are probably not the person who made the image. If a source is requested that would be reasonable as well.
But that is a question only @NuttsnBolts can answer, as I'm no organizer in this.