These stuff objects will generate an AI of the given type. Each type has unique Health, Accuracy, Melee Damage, and Speed. Once an AI has been placed, you can use their context menu to alter their weapon, inventory, and patrol path. Patrol path wait times at each point can be set in the AI Settings modal, found in an AI's context menu.
MilitaryMech is a special boss-type AI. This AI does not move, and comes equipped with a rocket launcher and turret attachment. These attachments will attempt to target different players whenever possible, making it a great defensive mech. None of this AI's special settings will have any effect, except for its inventory value, which will be dropped when destoryed.
Civilians, both Aggressive and Passive, will generate a random hair style and color in-game. Aggressive civials behave the same as other AIs. Passive civilians will only become alerted by being damaged, and sound triggers (gunshots and such). When a passive civilian becomes alerted, they will simply run away from whatever alerted them. They will eventually timeout and return to their non-alerted patrol path, just like a standard AI.