A word of warning to all you aspiring sorcerers out there: if you're thinking about dabbling with the Sigillum Dei, you better know what you're getting into. This ancient magical seal, with its origins dating back to the 14th-century Liber Juratus, was popularised by the 16th-century occultist John Dee.

The Sigillum Dei or ‘Seal of Truth’ is said to grant the wielder the power to communicate with angels, control the elements, and even become the 'Living' God among humanity. The Liber Juratus specifies the exact dimensions of the circles, ranging from three to nine fingers in diameter, each with its own symbolic meaning.

But before you start inscribing circles and pentagrams on your coffee table, remember: precision is key. One wrong move and you might just summon a demon. Best of luck!