When Sonic Boom's art was first revealed, fans took immediate notice of the huge change that Knuckles went through and Sonic's new Nathan Drake-esque scarf. But compared to recent concept art revealed for the game, those are relatively tame changes to the Sonic crew.

Artists Craig Harris and Nicolas P Villarreal recently posted concept art they did for Sonic Boom to their Facebook pages. Discovered by gaming forum Neogaf, the images show a wide range of art styles and could have resulted in a very different direction for the franchise.

Harris posted the following sets of images with accompanying descriptions:

"Needless to say Sega wasn't down with these..HAHA.."

"This game finally came out...halleluja...congrats guys!! One of my concepts for the hub. Sonic the Hedgehog...Sonic Boom!!" -- Harris

Villarreal wrote, "SONIC BOOM: Rise of Lyric released - We had an amazing team working together with Armand Serrano, Sylvain Deboissy, Eytan Zana, Craig Harris, Yuki Demers, Jason Norton and Hugo Martin. Some concepts below:"

You can see more of Harris' work at his official webpage, and Villarreal's website is here.

But what do you think about the concepts? Anything stand out that you wish would've made it to the final game?

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