Casio has announced that the G-Shock brand will be sponsoring the Secret Wars Euro League events. These competitions are basically a one-on-one artist duels where the two challenge each other to make the best piece of artwork.

The rules of the battle are simple: There are 90 minutes on the clock; during which an artist is placed either side of an invisible line. Only black paint can be used on white walls, with no sketches or pencils allowed! The battles are judged by two guest judges and a crowd vote, which is measured using a decibel reader. A clean and fair fight to find the best of Europe’s burgeoning artistic talent.

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Here's a video of what these events look like.