E-100 Series

The E-100 Series line of robots were the first of the E-Series created by Dr. Eggman. They were gunner robots, still the in developmental stages. Almost all were equipped with some sort of lock-on target ammunition, though its utility varied between models. All of the E-100 series were given Greek letters for code-names. The most famous of these was E-102 Gamma, who eventually overcame his programming and rejected Dr. Eggman.

Creation and Demise
Most of the original E-100 Series were put to little use prior to being destroyed. The original line-up of E-100s were first put into a competition with each other to retrieve Froggy who had absorbed Chaos' tail. Gamma located Froggy at Big the Cat's hut, knocked the feline over and captured the frog. When he returned, Eggman was delighted to see Gamma's success, while the other E-100s had all failed and brought back regular frogs. With Gamma as the victor, Eggman disposed of the other E-100s and assigned Gamma to his next mission: retrieving a Flicky from Amy Rose. (StH: #80, #81, #82)

Later Models

 * See: E-105 Series

In 3236, Dr. Eggman employed a series of E-105 robots as an army to invade Feral Forest. These robots were very unsuccessful, as the local villagers along with Sonic the Hedgehog, Sally Acorn, Geoffrey St. John and Hershey Cat managed to destroy the entire E-105 army with relative ease. (StH: #121)

Robots similar to the E-Series were also seen among the robots sent to the ruins of Robotropolis with the intention of breaching its force-field and allowing nuclear waste to spread to Knothole. Like the other robots, they were also repelled by an all-out assault led by Knuckles the Echidna, Amy Rose, Rouge the Bat, and General Armand D'Coolette. (StH #132, #133)

Abilities
These 'bots are built for battle. Thier main weapons usually consist of machine guns and cannons on thier arms. E-103 and the unnamed purple E-100 are equipped with double the firepower thanks to having two cannons on both arms.

E-102 Gamma has help shooting thanks to a lock-on laser targeting device on his head. Due to the targeting device, Gamma's shots are almost always accurate, and allows for pinpoint accuracy to find an enemy's weakspot.

Gamma is also equipped with a jet booster that allows him to hover for some time and cross longer distances in the air, making him one of the more resourceful E-100 robots.

The E-105 Series' basic combat abilities consist of laser cannons on their arms.

Known E-100 robots

 * E-102 Gamma
 * E-103
 * Unnamed yellow E-100 Series robot.
 * Unnamed purple E-100 Series robot.
 * E-105 Series

Background information
In the Sonic game universe, the E-100 Series is considerably larger and all had code-names from the Greek Alphabet, including E-100 Alpha (α), or ZERO, E-101 Beta (β), E-121 Phi (φ) and E-123 Omega (Ω). In the comic adaptation however, only E-102 Gamma and E-103's names were specified, and E-103's name could only be seen on his body.

In the game universe, E-103 is called E-103 Delta (δ), the yellow E-100 robot is called E-104 Epsilon (ε) and the purple E-100 robot is called E-105 Zeta (ζ). But since none of this was mentioned in the comic, it is not considered canon by this site's canon policy.

None of them should be confused with Isaac, despite it being referred to as an "E-100 approximate" by Metal Sonic.