Sonic the Hedgehog 4: Episode I

Sonic the Hedgehog 4: Episode I is a video game in the Sonic the Hedgehog series.

Plot
After saving the Master Emerald, and the Death Egg destroyed, Sonic decides to part ways with Tails in order to explore new worlds on his own, but it's not long until a vengeful Dr. Eggman lures Sonic back into a confrontation once more.

Gameplay
Much like the other traditional 2D Sonic games, Sonic the Hedgehog 4: Episode I allows Sonic to run, roll, spindash and bounce off springs as he explores the world.

The major addition to this game is Sonic's ability to use the homing attack from the 3D titles, although the game also makes heavy use of

The special zones in this game are very similar to the ones in Sonic the Hedgehog (or Sonic 1) which involve Sonic being guided through a maze in order to obtain a Chaos Emerald. Two additions to this special zone are Ring Gates, which block Sonic's movement before he obtains a set number of rings to progress and a time limit, putting the pressure on players to guide Sonic fast through the maze.

Collecting all the Chaos Emeralds will allow the player to unlock the true ending which leads into Sonic the Hedgehog 4: Episode II.

Collecting 50 rings will allow Sonic to turn Super Sonic if he has all the Chaos Emeralds, although due to the boss fight acts having less than 50 rings this does mean he can't fight the bosses as Super Sonic.

Trivia

 * This is the only game that allows players to exceed the usual 99 lives cap. The new cap is 999 lives.
 * Super Sonic in this game does not gain additional lives from collecting 100 rings.