In the past months we've shared some videos from the Did You Know Gaming YouTube channel, which takes well-known and loved franchises and digs out some interesting facts and quirks for us to enjoy. These typically involve buried lines of code that reveal abandoned development ideas, or just snippets of information about concepts left on the cutting room floor.

The latest franchise to get the treatment is Sonic the Hedgehog, the sworn enemy of Mario and Nintendo during the 16-bit era, in particular. That's all changed, of course, and Sonic and Mario now regularly meet up for some competitive Olympic sport and high-fives, with the spiky one even being kind enough to let others have a chance in the 100-metre sprint. The animosity is gone, so we feel that we should all be able to avoid looking back in anger.

So here it is, with some facts on Dr Eggman's origins — or Dr Robotnik as he's known to older gamers — some hidden concept art in Sonic CD and more: check it out below.

Thanks to Shane Gill for the tip