Engineer
EM Electrocution Build
This is your typical electrocution damage build using “Stubby”. Perk choices compliment the overclock, but there is a second overclock option if you don’t want to use EM Refire Booster. This build really works well in a group game were allies have increase damage against enemies affect by effects. (Scout Bullets of Mercy build for example). I believe there are better solo builds available, but this build still remains a top contender. The ability to apply electrocution to a large group with both weapon options, paired with our increase damage primary to all electrocuted enemies makes this a very reliable build. If using EM Refire Booster, engage enemies in close to mid range since the “Stubby” has pretty bad weapon spread and is hard to shoot accurately from a distance.
Weapons
“Stubby” Voltaic SMG
T1B – 
Upgraded Capacitors (+25% Chance to Electrocute)
T2B – 
Recoil Dampeners (-40% Recoil)
T3B – 
Expanded Ammo Bags (+120 Max Ammo)
T4B – 
Conductive Bullets (+30% Damage vs Electrocuted enemies)
T5B – 
Electric Arc (25% Chance to electrocute enemies around the primary target)
EM Refire Booster (+2 Electric Damage, +4 Rate of Fire, +50% Spread)
The “Stubby” really shines with electric focused damage and electrocuting enemies. Enemies that are electrocuted take more damage from the “Stubby”, applying electrocution as fast as possible becomes a priority. There are 2 options for Overclocks if you really want to, in the end, they are very similar and function nearly the same way. The alternative overlock is Light-Weight Rounds. Change to T3A for increase damage because this overclock adds 180 max ammo at the cost of fire rate.
While both overlocks are nearly the same, I do still recommend EM Refire Booster since it adds electric damage and the focus of this build is electric damage. The choice ultimately is up to you and your preferred playstyle.
Breach Cutter
T1A – 
Prolonged Power Generation (+1.5 Projectile Lifetime)
T2B – 
Condensed Plasma (+175 Beam DPS)
T3A – 
Quick Deploy (-0.2 Plasma Expansion Delay)
T4B – 
Disruptive Frequency Tuning (+100% to Stun for 3 seconds)
T5B – 
Plasma Trail (Leave behind a plasma trail, deals damage for 4.6 seconds)
High Voltage Crossover (100% Chance to electrocute enemies, 16 Electric Damage per second for 4 seconds, -33% Magazine Size)
Breach Cutter is the best secondary to use with the “Stubby” without question. It does a lot of damage on its own, dealing with Praetorians with ease, and with our overclock, guarantees application of electrocution to any enemy it hits. High Voltage Crossover pairs really nicely with the “Stubby” since our primary weapon does more damage to any enemy electrocuted. This allows Breach Cutter to have 2 roles in this build. Use it to deal with Praetorians and Oppressors, or, to apply electric damage to a large horde all at once and cleanup with “Stubby” once the group is electrocuted.
Equipment
LMG Gun Platform
T1A – 
Gemini System (+1 Max Turret, +90 Carried Ammo)
T2B – 
Quick Deploy (-2 seconds to Construct)
T3B – 
Stun (+20% to Stun)
T4A – 
Defender System (+5 Damage, Increase )
Gemini System (T1A) allows more coverage, on more angles and does more total damage when combined. While the MKII turret offers more damage, if both Gemini turrets are shooting the same target, they do more damage overall. Being able to damage 2 separate targets or to cover 2 different angles is more valuable then 1 enhanced turret.
Platform Gun
T1B – 
Expanded Ammo Bags (+8 Max Ammo)
T2A – 
Plastcrete MKII (Reduce Fall Damage)
T3B – 
Repellant Additive (Bugs avoid walking on platforms)
Main points here are the increase in ammo, and bugs avoiding the platforms (when possible). T2 only has one option so there is no choice to be done. Option to take more ammo instead of the bug repellant (T3B) since the bugs will walk on the platforms if they need to regardless of the repellant.
Owl Amor Rig
T1A – 
Improved Generator (-1 Second Shield Recharge Delay)
T2B – 
Healthy (+20 Max Health)
T3A – 
Hazmat System (+50% Poison Resistance)
T4C – 
Breathing Room (+3 Second Revive Invulnerability)
Armor is pretty flexible in perk choice, I enjoyed the following perk combination. It will always be more beneficial to take T2B (Healthy) for the increase in health, rather then shield, which only gives +5. Shield also regenerates, while health does not unless you gather red sugar or a re-supply pod. I also found T4C to be helpful especially on harder difficulties were you might be revived in the middle of a horde of enemies, the extra seconds in invulnerability will really help to get to a safe distance to re-group.
Lure
OR
Shredder Swarm
The Lure grenade offers great versatility with engineer builds. It’s main quality is distracting enemies, while it does have a small explosion at the end, it does not do a lot of damage. The Lure is really helpful on higher difficulties to help with repositioning, getting a revive, or to just cluster enemies together for an explosion.
The new Shredder Swarm grenade is also really strong but is more a damaging grenade, rather then a utility grenade. The grenade will spawn a group of shredders that rip through bugs with very decent damage. They won’t do very much against a Praetorian, but will definitely help out in a horde.
Passive Perks
Thorns
Resupplier
Elemental Insulation
Deep Pockets
Thorns : One of the better perks for the Engineer, since we don’t have any great crowd control against swarmers and alike (unless your turrets are up or you want to spend precious secondary weapon ammo, this perk really helps up out. It is capable of killing small enemies instantly after they hit us. It helps the overall crowd control capabilities. Definitely worth grabbing.
Resupplier : Another great perk that I recommend across all classes. If resupplying 50% faster wasn’t good enough to have in a pinch, gaining 25% more health each time is just the cherry on top. One of the best passive perks to have in my opinion.
Elemental Insulation : An optional choice, but a relatively strong one depending on the cave biome you’re in. Take 30% less damage from all elemental sources. This includes; Fire/Frost/Electricity/Poison/Radiation/Heat and Cold.
Deep Pockets : Another optional choice, this is more a quality of life perk choice, it allows you to hold +15 more minerals of each type. This can be particularly helpful when gathering resources from hard to reach places, and in general limit the amount of trips needed to deposit them. This especially shines in any mission that does not have a Molly.
Active Perks
Iron Will
Field Medic
Dash
Beast Master
Iron Will : Once per mission, you can revive yourself for 12 seconds before going back down. This may not sound like a great perk at first, but it can be a game saver. While on it’s own, not very strong, you can revive allies who can then revive you in turn. Alternatively, even in a solo game, there is a way you can stay alive, effectively turning this into a permanent self revive option. If you gather health within the 12 seconds, you will stay alive. This can be from Red Sugar, Resupply pods, or other means (Vampire Passive Perk). This perk is pretty strong on any class to keep for emergency situations. Recommended saving it’s use until absolutely necessary.
Field Medic: 100% a group game perk, do not use if playing solo. This perk should definitely be equipped when playing in a group game. The ability to revive allies 30%, fear enemies after reviving an ally, on top of the activation option of instantly reviving an ally, this perk can save games on its own.
Dash : Gain a very short burst of speed that can be used every 25 seconds (at max rank). This burst of speed ignores any slow effects you may be suffering, which can be really helpful when stuck in goo or any other slowing effects. You can even Dash while holding heavy objects like Aquarqs. This is particularly strong on slower classes, like the Engineer, in order to keep up with the team, or to escape a tight situation quickly.
Beast Master : A generally fun, and useful support perk, I found it’s best use in solo games, but it is not restricted to this mode. This perk allows you to convert a “Grunt” level enemy to be a companion. This includes “Grunts”;”Slashers” and “Guards”. I found Guards to be the best ones to grab, from the available options. It has the most health, which means, will survive the longest while grabbing enemy attention. In a pinch, the Slasher is also very helpful as it has the most damage to kill enemies from the available options. In the end, this is up to personal choice. There is a 5 minute cooldown between uses, allowing you to repeatability use this perk.
