GameVideos provides us with a first look at leaked Sonic the Hedgehog 4 — will be released summer 2010 — gameplay. This title “follows the adventure of the series’ main protagonist, Sonic the Hedgehog, taking place after Sonic & Knuckles.” Video after the break.

The game will be a two-dimensional side-scrolling platformer reminiscent of the original Sonic games with an emphasis on speed. Players will control only Sonic the Hedgehog, using control mechanics such as the original spin dash and power-ups including Speed Shoes, alongside moves such as the homing attack seen in the 3D entries in the series.

[via Crunchgear]