Sonic was considered relatively low tier in Super Smash Bros. Brawl, but that hasn't stopped him from placing well in a few majors here and there. Still, the Sonic we'll receive when Smash Bros. Wii U hits has seen quite a few changes, both positive and negative. Let's cut to the chase and cover what exactly you should expect from the new Sonic.
We'll start with Sonic's aerial attacks. His forward air is a little faster, and can be immediately canceled as soon as he lands. The speed buff is interesting to think about since Sonic already had a fast forward air attack. This is a fairly decent buff to his aerial game, but that's not all. His back air is easily his best KO attack, having more knockback and a bit more hit stun as well. It's a little bit harder to connect with, possibly due to a smaller hitbox, but it shouldn't be too difficult for most players to make the proper adjustments.
Sonic's down air spikes the opponent downward if you connect right at the sweet spot. This makes it another good aerial KO attack, but unfortunately the recovery on it is much longer. When Sonic hits the ground there's significantly more delay compared to Brawl. However, his up aerial has more knockback and hit stun like back air, but also has more horizontal range.
Looking at his special moves, first and foremost, you can still Vertical Spin Dash Jump (VSDJ). This shouldn't be surprising, but competitive Smash players should be happy to know it's still available to Sonic. In addition, Sonic's side B and down B are now faster. With the increased speed to down B, Sonic's pressure game is significantly improved. There's also less knockback (which is a good thing), allowing for Sonic to easily combo after the attack.
Unfortunately, Sonic's general recovery has been nerfed a bit. The spring doesn't lift Sonic as high into the air as it did in Brawl. What could be his biggest nerf is the complete lack of an Aerial Spin Charge Shield Cancel. You can no longer shield cancel Sonic's aerial Spin Charge. However, with the buff to his side B, and the VSDJ still available, it's not the end of the world for Sonic players.
So far, it seems as though Sonic is a generally improved character. His Smash attacks are all mainly unchanged, although his forward Smash executes a bit slower and has a longer recovery. Even with that slight nerf, he has plenty of KO attacks between his buffed aerials and everything else he had in Brawl. It's a bit early to determine is Sonic has the potential to be a top tier character, but at the moment he should be able to hold his own against most of the cast.
Stay tuned to Prima Games as we'll have more information on Super Smash Bros. Wii U coming your way in the near future.