It's Ninetails! I actually did a lot of sketches of Ninetails during Sometober, but I didn't want most of my choices to involve him so I kept it down to just the ones I really liked.

Ninetails is dressed up for Halloween. It would appear he's selected E-10000P from Sonic Freeriders to dress as this time. For those who don't know, the E-10000 are a line of Eggman Robots that are designed explicitly to airboard. E-10000P is exclusive to the multiplayer modes of Sonic Freeriders and is thus heavily obscure, but he's pink so he's my favorite by default. XP

Those with a keen eye will notice I took elements from this costume and worked them into Ninetails' SRB2K Kart Crew outfit.