Eggman's Forces are simply Eggman's robots. It's comprised of only one robot, the Egg Fighter, because unfortunately, I could only find images of the Egg Fighter.
When the Egg Fighter spots a fighter, it runs towards them and performs a spinning attack as it rotates on it's torso.
Some Egg Fighters Possess shields. In these cases, they will attempt to push fighters with their shields. These attacks do no damage unless the shield is electrified. Either way you must get to the behind them to attack them and use Trophy Stands on them.
Some Egg Fighters who possess shields, also possess swords. In these cases,they will run towards you and slash at you with their swords.