Egg Pawn

The E-1001 Egg Pawn, usually referred to simply as Egg Pawns (エッグポーン), first apeared in the game Sonic Heroes and are a part of Dr Eggman's E-Series, his latest series of Badniks. They come in different varieties, each having its own unique abilities, and serve as Eggman's foot soldiers. They also may come equiped with a lance, machine gun, or laser. Some of them have shields that can come in three diferent styles: rock, metal, and heavy metal. Egg Pawns carrying lances will charge you while the ones wielding lasers and machine guns will fire without changing position. These weapons can also be used by Shadow in the game Shadow the Hedgehog. They can be picked up from defeated Egg Pawns. The Egg Pawns are also the first type of Eggman Robots that are not powered by animals.

Egg Pawns also serve as enemies in Sonic Rush. This time, they had different colour schemes to match the weapon (or, indeed, no weapon) they carried and in this game they're powered by Animals unlike the other games.

In Sonic Heroes, there was also another enemy known as the Egg Flapper. These enemies look similar to Egg Pawns, except they fly. Again, they were featured in Sonic Rush. and they also appear in Sonic and the Black Knight as enemies in the legacy missions. They serve as the only enemies that can be destroyed with a homing attack. The Egg Flappers cannot be destroyed by any sword attacks, possibly due to not being in Arthurian Legends.

The Egg Pawn also shares more than a passing resemblance to EggRobo. Also new enemies in Sonic Unleashed called Egg Fighters and its variants seem to be the equivalent to Egg Pawns as they bear a similar appearance.

The Egg Pawns also appear in Mario & Sonic at the Olympic Games as enemies that the player can shoot in the Dream Shooting competition. In this game, Egg Pawns are similar to Goombas from the Super Mario series.

The Egg Pawns also appear in the Wii and DS exclusive Sonic Colors as common stage enemies as seen in gameplay trailers. Like in Sonic Heroes, their design is different based on every level.

They will appear in Sonic Generations also. So far, they have only been confirmed for Seaside Hill, buttey will likely be in Planet Wisp also.

Egg Knight
The Egg Knights are gold plated Egg Pawns that typically wield lances and lead a small group of Egg Pawns. They have more stamina than ordinary Egg Pawns and are usually found in positions where it is difficult to reach them without alerting any regular Egg Pawns nearby. This is because the destruction of an Egg Knight will result in any and all Egg Pawns in the nearby area being automatically destroyed with it.

Casino Pawns
These are neon pink or blue Egg Pawns that have bunny ears, wierd meters above their heads, and typically wield machine guns. They appear in the fifth and sixth levels of Sonic Heroes.

Weapons and Equipment
Egg Pawns wield rapid fire blasters, single shot cannons and lances in Sonic Heroes, semi automatic blasters and bazookas and lances in Shadow the Hedgehog (they use the same models from Heroes) and in Sonic Heroes, Egg Pawns also carry shields sometimes which can be rectangular, round with spikes, or stone.

Trivia

 * Other than their appearance in Shadow the Hedgehog and their minor appearance in Sonic and Sega All Stars Racing, the Egg Pawns are primarily Nintendo exclusives only appearing on Nintendo consoles. They had seemed to be replaced by the Egg Fighters in Sonic Unleashed which was cross-platformed, but were brought back in Sonic Colors which was Nintendo exclusive.
 * The Egg Pawns only really appearing on Nintendo consoles could be because of their relatively bland and stocky body which is easier to render on a non-hd console than a more detailed and slender robot.
 * The Egg Pawn being brought back for Sonic Colors could be because of their less menacing look. Eggman probably wanted more friendly looking robots to work at the Interstellar Amusement Park so people wouldn't suspect his evil plans.