The Special Agent is a "new unit" introduced in a short mission. Perkins comes running to Lt. Morgan, saying that some Silver Wolf saboteurs are attacking the camp. Morgan gives orders to engage them, but Perkins says that someone already is.
Morgan: "Wait, someone? This I have to see"
A battle then ensues involving Morgan, three heavy tanks and two Special agents, among various other units. Once the battle is over, Floyd explains that these Agents were part of the Empire's secret divisions, and could penetrate front lines like butter. Perkins says that the Agent wants to sign up, but was not sure, because the Agent was speaking in code. However, Morgan gave an answer in plain English: YES!
The Special Agent is a premium unit that was available for a limited time for 80.
The Special Agent starts with an arsenal of 3 exceedingly interesting attacks, as well as the 3 ability slots to use them all at Rank 1. The Pistol weapon deals -type damage, making it interesting in that few units have resistance. The attack targets from the back, so blocking units placed in front of more vulnerable targets are of no use. Lastly, the damage on this Silent Strike is moderate-high, enough to make any unit worry due to its high critical chance.
The EMP Burst attack targets the entire battlefield, ignoring even blocking units, and affects Vehicles, Metal (which includes most Tanks), and Air units, dealing mild damage with the added chance of stunning its targets.
The Nerve Gas attack targets the entire battlefield as well, but only affects infantry units (i.e., Soldiers, Critters, Civilians). Like the EMP Burst, this attack also deals mild damage with the chance to inflict the Stun status. This attack can potentially shut down an infantry army.
Whatever the two battlefield-wide attacks weaken, the Pistol's Silent Strike will finish off. The Special Agent is an excellent support unit with a serious punch, but unfortunately players will have to wait until its purchase becomes available again, or hope to get it from a Secret Vault. In the meantime, the Field Agent is almost exactly the same, albeit much weaker.