Melee-Dependent Sentry Type (much like the Mini-Sentry is with the Gunslinger)
PDA's would change type of drone (i.e. A PDA that offers mini-buildings (Handy Partner) would make the drone a Mini-R-CAT, & whatever offers stuff that goes with a the Artillery Sentry would make this an Artillery R-CAT)



( + )
+25 Max health on wearer
Drone is player-controlled
User is backstab & headshot resistant until the second hit
+100% Dispenser health & ammo restock range
+25% Teleporter recharge



( | )
Replaces Sentry with an R-CAT Drone.

Lvl. 1 - 100hp + needle cannon
Lvl. 2 - 150hp + dual needle guns
Lvl. 3 - 175hp + mini-rocket launcher

On 3 kills: Sentry upgrades to Lvl. 2
On 6 kills (total): Sentry upgrades to Lvl. 3



( - )
-25% Sentry damage penalty
On Use: Sentry & player is highlighted to enemies.
Sentry self-destructs on first backstab or headshot from an enemy on user
Sentry self-destructs when sentry ammo runs out or crashes into enemy



This is for those who wanna get an "upper hand" in combat, while the dispenser & teleporter upgrades are so you don't forget what your job is.