- Main article ATP Mark II Peacekeeper
On April 5,1992, reports of Meat Puppets being ineffective compared to human infantry were flooding ATP High Command. In response, an initiative to upgrade the Meat Puppets began. The ATP Research & Development Branch started to analyze the Meat Puppet's performance on the battlefield . The first thing that the researchers discovered is that Meat Puppets can't operate on their own, usually they require a human officer to give them orders. Second, Meat Puppets don't utilize their weapons effectively, chewing through their ammo to eliminate a few targets. To remedy both of those issues, the researchers decided that the improved unit would require an AI for it to operate independently and learn from its mistakes.
In November 23, 2003, after years of development, an AI chip was created and implanted into all Meat Puppet units. The outcome is a huge success, the Meat Puppets were able to act and "think" like human beings, improving their abilities to act outside the command of a commanding officer while learning to be more efficient with firearms. An unintended result of the newly acquired ability to learn is that the Meat Puppets themselves began to become self-aware. R&D at first were alarmed of the possible consequences of self-awareness, but decided to implement it into all units upon learning that the Meat Puppets could take the role of essential personnel thanks to it's ability to retain a large amount of memory. From there the researchers decided to create an entirely new unit with an original AI.
In November 25, 2003, development was underway to create an entirely new unit using an AI based on the original developed for the Meat Puppet. The first priority of the project was to increase the learning speed of the new infantry to accelerate the self-awareness process and the second priority is to increase the combat effectiveness of the unit, making it excel past its predecessor in terms of lethality, weapons flexibility, and the ability to act human. The developers discovered that they can't make the new unit be as flexible as the Meat Puppet in terms of specialization. As a result they decided to divide the one unit into three specialized units, each with a different role. The three units are to specialize as reconnaissance, anti-personnel, and anti-vehicle, turning into the "Stalker", "Peacekeeper" and ATP Mark II "Hellraiser" projects respectively.
The Stalker Project
The Stalker was completed on December 24, 2011. The unit was designed be be more agile than the average Peacekeeper while sacrificing most of the latter's protection. The Stalker is significantly more proficient in melee combat compared to other units in the event where firearms are unavailable or if stealth is necessary. Its standard weapon is either a submachine gun or a carbine due to their compact size and portability.