DC Entertainment Co-Publisher Jim Lee has been known to hold scavenger hunts at Comic-Con International and C2E2, dropping visual clues on Twitter to direct his fans to hidden character sketches. For this Comic-Con, however, he'll celebrate his fast-approaching 50th birthday (it's on Aug. 11) by giving away 50 previously drawn sketches at his spotlight panel on Sunday.

"I can do a sketch, it's like a very complicated signature -- so I think the quickest sketch I can do is like a minute and a half," Lee tells DC All Access. "So I'd have to do it, literally, in two days."

In the video, below, he also reveals the secret origins of his Batman cover for the Comic-Con souvenir book.

"Y'know, sometimes covers come about in strange ways. So, they needed a Batman cover, and the first artist they wanted couldn't do it," Lee says with a laugh. "And so it fell upon me. [...] So, I have no dignity, so I said, 'Sure, I'll do it,' and had a preexisting piece I had done for a friend, so I called him up and said, hey, do you mind if this were to be on the Comic-Con cover for all these fans to see."

There's more in the DC All Access video. Comic-Con International begins Wednesday with Preview Night. Lee's spotlight panel will be held Sunday at 11:15 a.m. in Room 6DE.