Egg Keepers are the evolved form of the Egg Guardian. Immediately discernible by their crimson paint, Egg Guardians pose a greater threat thanks to their increased speed and armor. Egg Keepers attack with either ﬁsts or spheres—same as the Egg Guardian—but do so with heightened ferocity. — Description, Sonic the Hedgehog: Official Game Guide
The Egg keeper's design is similar to that of the Egg Guardian's, but with a red and grey color scheme. Much like the Egg Guardians, they have a red core in the center of their bodies which serves as their weak spot. Also, like the Egg Guardians, they have either ﬁsts or spheres as hands.
The Egg Keepers can attack with either fists or spheres. When they launch their fists, they will follow the playable character for a short time before exploding. After their two fists/spheres are destroyed, they will begin rotating and start shooting two volcanic lasers before their arms automatically regenerate.
Like the Egg Guardians, the Egg Keepers cannot be paralyzed by Psycho Shock or Psycho Smash until their two fists or spheres are destroyed. When hit while it has no arms, the Egg Keeper will fall over and eject its energy core. Repeated strikes to the core or use of Silver's Psychokinesis will destroy them. To deal damage without getting hurt in Sonic and Shadow's case, the player must attack the Egg Keeper before it launches its fists, as it will either hurt the player from its explosion or when it falls.
Powers and abilities
The Egg Keepers possess speed, armor, and strength greater than the Egg Guardians, and are far more durable as well. They are also able to launch either the spheres or fists they have for hands as projectiles (the latter of which can home in on enemies) and fire volcanic lasers from their arms.