|Technician: Engineer||Tier 4|
|Basic (4 pt): You can now carry 1 extra sentry gun.|
|Ace (8 pt): You can now carry an additional 2 extra sentry guns.|
This skill increases the amount of sentry guns you can carry on during a job, from 2 sentry guns (basic) to 4 (ace). This skill affects both the Normal and Suppressed sentry guns.
This skill is a must for any player who wants to invest in sentry guns, since it increases the defensive capabilities of said deployable. One with this skill can effectively guard one or more areas with the sentries well placed, allowing for crowd control, protect an objective, delay an oncoming force, etc. Enabling AP rounds is a good idea since it allows the sentry's shots to pierce through Shields and the chest plates of Maximum Force Responders.
Because of the increase in ammo consumption to deploy all sentries, one should consider using weapons with an efficient ammo pickup rate (such as Shotguns or Grenade Launchers). Alternatively, consider getting Extra Lead along with Jack Of All Trades to being able to switch from your sentries to an ammo bag should you need to recover your reserves. Fully Loaded and Scavenger are also a good option to increase the amount of ammo you carry and recover.
Since the Suppressed sentry gun counts as a different deployable, one can use Jack of All Trades to bring a total of 6 sentry guns to a job. Ammo consumption should, however, be considered since the user cannot bring an ammo bag to the job when bringing both sentries.
- The skill's name and effect are a reference to tower defense games, where the player must rely on tactful placement of multiple sentry towers to defend a mission critical area.