It's about Earth's future or Mobius' past. After the prelude which is mainly the title, the Freedom Fighters have a new
threat. A threat that is already overwhelming.
The Freedom Fighters decide to explore what's left of Robotropolis and the Supremor but are unaware of what has been
happening and find themselves in a bit of trouble after hearing Sonic's tale of his past.
Lighthead RETURNS! And he is after the Master Chaos Emerald once again! Rotor leaves from guilt and shame (from Part 3)
and Snively finds himself roboticized and helping out a new character who ALSO wants the Master Chaos Emerald. Knuckles has
his hands tied. Can Knux save himself from these threats and what does Lighthead have in store? Sonic and co. will also find
themselves involved as more twists are placed in their path.
Sonic, Tails and Knuckles make plans to go up to the RSupremor to regain the Master Emerald but before they can, conflicts
remain. Sally doesn't like the idea and Gore suddenly shows up in search for the Sword of Acorns and is VERY determined to get
it. It becomes shear chaos for revenge to recover what was rightfully theirs once at the RSupremor.
Sonic and Knux and Tails continue their quest through the RSupremor and encounter more then they bargained for. Eventually it
becomes too much for them and they are faced with a decision that will ultimately decide the fate of the solar system.
Meanwhile, terrebots are on the move and threaten the inhabitants of knothole. All remaining residents are forced to put up a
battle.
Sonic, Tails and Knuckles now lighgrecized find themselves in their biggest challenge yet with the fate of their planet and
sun in the balance. The Star X Conquerors return to face off with the RSupremor. Explanations are made of their attacks.
Intelligence suggests Otrebor & Snively were involved with the onslaught with terrebots and the Freedom Fighters go in
search of them but when Knuckles catches them on the premises of the Floating Island, things get way out of hand. Meanwhile,
CHAOS comes up with a plan to accelerate the Master Emerald’s aging process to become the Eraos Emerald but fails to tell Lighthead.
C.H.A.O.S goes in search for more power in Robotropolis and manages to get this power in the form of Master Chaos. With
Lighthead and the Freedom Force on their way to the Floating Island and only the core Freedom Fighters to stop Master Chaos
from gaining the Eraos Emerald, its going to take way more than first thought to stop him, that is if you can stop a 6
dimensional being.
Three years have past since the events of HEBM X. Mobotropolis has been reclaimed and peace restored throughout the planet.
A discovery leads them to the center of the universe where trouble awaits. Master Chaos is back as well as the Rwerviums and
it'll be the most of unlikely occurences to finally put them to rest.
