Sonic the Hedgehog 4 is set after the events of Sonic & Knuckles. After Sonic manages to destroy Dr. Eggman ‘s Death Egg and with Angel Island back in the sky, he decides it is time to take a much deserved break. After parting with his companions Tails and Knuckles, Sonic sets off to explore new territories alone.
However, unbeknownst to him, his nemesis, Dr. Eggman, has survived their last encounter, and has revisited and improved some of his very best robotic creations in another attempt to defeat Sonic. Sonic must travel through a variety of zones to defeat Dr. Eggman once again.
Bellow you can see the release date and system requirements: