Sonic the Hedgehog Genesis is a Game Boy Advance port of the original Sega Genesis game, Sonic the Hedgehog. The port was released in November 2006 to commemorate the Sonic the Hedgehog series' 15th anniversary, but it was quite poorly received due to its poor sound quality, performance issues, poor graphics (due to technical limitations), and the physics.
The port also introduced Anniversary Mode and a game save feature. There is only one feature in Anniversary mode, and it is the Spin Dash, first introduced in Sonic the Hedgehog 2.
I have never seen anyone TAS the whole game before so I made a complete playthrough of all seven stages. This TAS takes advantage of both the spin dash and the broken physics in the game, including: momentum preservation, bunny hopping, slope boosting, stopping on a dime, and many more.