engineer
- Construct, maintain and upgrade a frail yet devastating sentry gun.
- ―Store Description
Description
The Engineer is a hardcore tower that attacks enemies with a rebar launcher and can build sentries within its range to assist with defense. It can be purchased from the store for 
2,250.
The Engineer can only be placed if its build range overlaps with the path. The Engineer generates scrap with each shot, and build a Sentry 1.0 automatically after obtaining 20 scrap, taking 3 seconds to build. Scrap is also used to repair and upgrade the sentry, which will be built on the path. The Engineer also has 100% sell value.
The sentry has five hit points. Two hit points are depleted whenever an enemy collides with it, or it is hit by an enemy attack. There is a 1 second invulnerability period after the sentry is damaged before it can be damaged by enemies again. Every wave, the sentry also passively loses two hit points (excluding the Sentry 6.0). Hit points are restored by repairing the sentry, or if the sentry manages to upgrade to the next level. Once the sentry runs out of hit points, it is destroyed and has to be rebuilt from base level again.
The Repair ability consumes all stored scrap to repair the sentry's hit points; doing so will put the Engineer and sentry on standby for 5 seconds. Repair is disabled with a Sentry 6.0 active. The Upgrade ability, unlocked at Level 2, will consume all stored scrap to progress the sentry's upgrade, and will also stall the Engineer and sentry for 5 seconds. Extra scrap will not progress towards the next sentry level and will be wasted. Upgrade is disabled when the sentry is at max level, which varies depending on the Engineer's level. The Shield ability, unlocked at Level 5, disables the Engineer and sentry, but protects the sentry from taking any damage from enemies.
The Engineer has a placement limit of one per player.
Upgrades
+1 Range 
+5 Damage 
2 > 1.7 Firerate 
+3 Scrap 
Sell Price changes to
+1 Range
+5 Damage
1.7 > 1.5 Firerate
+9 Scrap
+Upgrade Ability
•18 Damage
•0.5 Firerate
•19 Range
•Hidden Detection 
•5 Hit Points 
•1 Scrap Per Shot
•25 Repair Requirement
•250 Upgrade Requirement
Sell Price changes to
+15 Damage
1.5 > 1.2 Firerate
+8 Scrap
+Hidden Detection
•25 Damage
•0.3 Firerate
•20 Range
•Hidden Detection
•5 Hit Points
•1 Scrap Per Shot
•50 Repair Requirement
•500 Upgrade Requirement
Sell Price changes to
+20 Damage
1.2 > 1 Firerate
•25 Damage
•0.1 Firerate
•21 Range
•Hidden Detection
•5 Hit Points
•1 Scrap Per Shot
•100 Repair Requirement
•750 Upgrade Requirement
Sell Price changes to
+1 Range
+25 Damage
1 > 0.8 Firerate
+Shield Ability
•40 Damage
•0.07 Firerate
•22 Range
•Hidden Detection
•5 Hit Points
•2 Scrap Per Shot
•200 Repair Requirement
•1,000 Upgrade Requirement
Sell Price changes to
+50 Damage
0.8 > 0.55 Firerate
•60 Damage
•0.04 Firerate
•22 Range
•Hidden Detection
•5 Hit Points
•0 Scrap Per Shot
•1,500 Upgrade Requirement
•No longer takes passive wave damage
Sell Price changes to
Abilities
Consume all scrap to repair hit points for the sentry. The sentry and Engineer will be disarmed for 5 seconds while repairing. Disabled with a Sentry 6.0 active.
Consume all scrap to progress the sentry's upgrades. The sentry and Engineer will be disarmed for 5 seconds while upgrading. If the sentry upgrades to its next level, replenish all hit points. Disabled with a max level sentry active, which varies between Engineer levels.
Raise a shield for the Engineer and sentry, disabling both but protecting the sentry from damage done by attacks.
Stats Table
| Engineer Stats | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Level | Total Price | Damage | Firerate | Range | Build Range | Scrap Per Shot | DPS[1] | Combined DPS[2] | Cost Efficiency | Combined Cost Efficiency |
| 0 | |
5 | 2 | 16 | 8 | 5 | 2.5 | 11.07 | |
|
| 1 | |
10 | 1.7 | 17 | 8 | 8 | 5.88 | 14.45 | |
|
| 2 | |
15 | 1.5 | 18 | 8 | 12 | 10 | 46 | |
|
| 3 | |
30 | 1.2 | 18 | 8 | 20 | 25 | 108.33 | |
|
| 4 | |
50 | 1 | 18 | 8 | 20 | 50 | 275 | |
|
| 5 | |
75 | 0.8 | 19 | 8 | 20 | 93.75 | 665.18 | |
|
| 6 | |
125 | 0.55 | 20 | 8 | 20 | 227.27 | 1,727.27 | |
|
| Sentry Stats | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Level | Sentry | Hit Points | Damage | Firerate | Range | Scrap Per Shot | Build Requirement | Repair Requirement[3] | Upgrade Requirement | DPS[4] |
| 0–1 | Sentry 1.0 | 5 | 6 | 0.7 | 19 | 1 | 20 | 15 | N/A | 8.57 |
| 2 | Sentry 2.0 | 5 | 18 | 0.5 | 19 | 1 | N/A | 25 | 250 | 36 |
| 3 | Sentry 3.0 | 5 | 25 | 0.3 | 20 | 1 | N/A | 50 | 500 | 83.33 |
| 4 | Sentry 4.0 | 5 | 25 | 0.1 | 21 | 1 | N/A | 100 | 750 | 250 |
| 5 | Sentry 5.0 | 5 | 40 | 0.07 | 22 | 2 | N/A | 200 | 1,000 | 571.43 |
| 6 | Sentry 6.0 | 5 | 60 | 0.04 | 22 | 0 | N/A | N/A | 1,500 | 1,500 |