Engineer
Overload Build
The Warthog is a very solid weapon for the Engineer that really suits it’s role and effective fighting range when paired with turrets and the secondary weapon options. With Cycle Overload and the perk choices, we more then double the effective Rate of Fire for the Warthog, allowing this weapon to deal with both horde and single Praetorians swiftly. Deepcore’s mini nukes is also a very effective tool for both horde and single targets, however the sorely lacking amount of ammo means we need to carefully chose when to use it. Use your turrets as often as possible, they only take 2 seconds to rebuild anyways. When a horde is on it’s way, try placing them in effective areas that overlook the cave zone you’re in to get their max benefit. One of the major drawbacks of this build is the ammo economy, while it may make this a slightly harder build to get around, its damage potential in both a solo or group game make it a solid contender to use.
Check out the Dreadnought Variant of this build to effectively deal with Dreadnoughts specifically.
Weapons
Warthog Auto 210
T1A – 
Superchanged Feed Mechanism (+1 Rate of Fire)
T2B – 
Loaded Shells (+2 Pellets per Shots)
T3C – 
High Capacity Magazine (+2 Magazine Size)
T4B – 
Bigger Pellets (+1 Damage per Pellet)
T5B – 
Miner Adjustments (Becomes Full Auto; +0.5 Rate of Fire)
Cycle Overload (+1 Damage per Pellet, +2 Rate of Fire, +0.5 Reload Time, +50% Spread)
Cycle Overload with this perk choice makes this weapon an overall workhorse on any difficulty choice. The only downside will be your ammo levels. With only 90 bullets in higher level caves, you may notice an ammo economy issue. If you intend on using the weapon with it’s current perk choice, you will need to synergize your secondary weapon and turrets properly to ensure you don’t run out of ammo pre-maturely. An alternate change you cane make is to take a damage cut and select T2A to increase your max ammo. (Brings it from 90 to 132 total)
The main differences between the two are as follows;
T2B – Magazine Damage : 720 | Overall Damage : 8 820
T2A – Magazine Damage : 576 | Overall Damage : 10 080
Depending where you want your damage to be, upfront or stretch it out, take the option that best suits your playstyle.
Deepcore 40mm PGL
T1B – 
Extra Ammo (+2 Max Ammo)
T2A – 
Expanded Ammo Bags (+2 Max Ammo)
T3C – 
High Velocity Grenades (+180% Velocity)
T4B – 
Nails + Tape (+1m AoE Radius)
T5B – 
Spiky Grenade (+60 Direct Damage)
Fat Boy (x4 Area Damage, +1 AoE Radius, -70% Max Ammo, -30% Velocity, Leave behind 8m Radioactive zone for 15 seconds)
The Deepcore is essentially a mini nuke with Fat Boy overclock. One round from this grenade launcher can devastate hordes before they even have a chance to do anything noticeable. Be careful to not hurt your allies as this will leave a massive radioactive area around the impact zone. Not the best for single target damage, while it will still hurt any Praetorian (or stronger) enemies, we don’t take full benefit from the Fat Boys overclock, and our ammo capacity is severely small.
Alternate
Breach Cutter
T1A – 
Prolonged Power Generation (+1.5 Projectile Lifetime)
T2A – 
Expanded Ammo Bags (+6 Max Ammo)
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)
Return to Sender (Holding down the trigger activates a remote connection, release to cause the line to move back to the gun. -6 Max Ammo)
The Breach Cutter offers a slightly different solution to the Warthog ammo economy. Breach can both be used to clear hordes of enemies effectively with Return to Sender and Plasma Trail, or to Praetorians and Oppressors as it melts health bars. Compared to the Deepcore, we have much more ammo with the Breach Cutter allowing us to be more flexible for when we use it.
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.
