Emerald of Speed - The blue emerald. It grants the beholder the gift of seemingly impossible speed. It is guarded by Lien-da, though a fragment powers Radiation the Hedgehog.
Emerald of Strength - The red emerald. The holder's strength becomes enormous when it is used. It is guarded by Mobius A Dimitri (MxG).
Emerald of Mind - The green emerald grants its bearer untold wisdom. Mobius A Mammoth Mogul currently guards it.
Emerald of Light - The purple emerald controls both light and dark, in the literal and metaphorical sense. The guardian of this one has never been seen, just a silhouette. And it looked a lot like Singularity the Hedgehog's. But that's impossible! Right?
The Mobius A master emerald was split into four pieces long ago. Each piece became inhabited by a different spirit. The emeralds were guarded by the echidna tribe for a long time, but have since been kept by four villainous figures.
GuardiansMammoth Mogul is in Mobius A not a villain. Instead, he remains neutral. The emerald of mind is for his exclusive use.
Lien-da has the emerald of speed hidden carefully. Until the opportune moment...
Dimitri guards the emerald of strength with his life, and for good reason. He needs the power from it to stay alive.
And the fourth... who IS he anyway? He has the same outline as Singularity/Shadow. But Singularity isn't in any shape to be up and about!
- Since the chaos emeralds in Mobius A are all undiscovered or in constant use, the entropy emeralds are used to fulfill the same roles.
- The Entropy Emeralds are also due to appear in the fangame (not set in the Archieverse) Sonic Journeys.