As DC Publisher and Chief Creative Officer Jim Lee continues his charity auction for comics shops, he added a new watercolor portrait of Golden Age Superman to his growing lot of artwork.

"Golden Age Superman!" he wrote on Twitter. "Sketch 49. To benefit comic shops in need via [Binc Foundation]."

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The Superman illustration was suggested by previous bidder Benton Brown. The 9x12 full-color watercolor sketch features the Golden Age version of the Man of Steel looking towards the viewer as he breaks free from a set of chains. He pops against a lightning-filled red and yellow sky matching the colors of his costume. The sketch is currently available on eBay, with the bidding price at $13,088 at the time of writing. The proceeds will benefit the Book Industry Charitable Foundation to help comic retailers affected by the Coronavirus (COVID-19) pandemic.

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This Superman watercolor is the latest in a series of experimental sketches Lee is doing before returning to his standard pen and ink drawings. He previously did similar illustrations for DC Comics staple Wonder Woman and newcomer Punchline.

The DC Publisher's 60-day charity sketch auction has continued on with his own sketches while attracting contributions from veteran artists such as Mike Mayhew and Philip Tan. He recently auctioned off X-Men art to benefit Black Lives Matter.