One of the three core classes, while the Soldier focuses on martial prowess and the Adept specializes in biotics, the Engineer’s contributions come from their technical aptitude. While they’re limited to Basic Armor and Pistols, they have access to every tech talent in the game, including Decryption, Electronics, Damping and AI Hacking, which unlocks the Sabotage, Overload, Damping and AI Hacking abilities, respectively. Sabotage overheats weapons and deals damage, Overload disrupts shields and deals damage, Damping inflicts stun, prevents the use of biotic/tech abilities and deals damage, and AI Hacking turns synthetic foes against their allies. Suffice to say, the Engineer has a variety of ways to deal damage in an area and debilitate enemies at the same time.
Engineer Bonus Talent
When it comes to bonus talents, the Engineer is spoiled for choice… mostly because they’re lacking quite a few things. First, their defense is pretty poor, as they can’t wear anything heavier than light armor, nor can they spend talents in any weapon besides the Pistol. While they have a great number of tech abilities, tossing Lift into the mix can further improve their arsenal by allowing them to render almost any foe in the game helpless for a few seconds. If you’d rather shore up the defense of your Engineer, Barrier is a fine choice, while as far as weapons go… well, Pistols aren’t all that big of a compromise, and seeing as you’d have to beat the game to unlock new weapon talents, you might as well just pick between the aforementioned Barrier or Lift talents.
The Engineer only has access to Pistols, which are perfectly serviceable mid-range weapons whose lackluster damage output is made up for by relatively good accuracy. There’s no pressing need to give the Engineer a new weapon talent tree via a bonus talent, and since you don’t have any other options, you may as well max it out. Any character with a decent pistol and Master Marksman is a significant threat, after all.
The Engineer’s progression is pretty straightforward: they start out with Decryption and Electronics unlocked, and you should advance in both of those talents until you unlock Advanced Sabotage and Hacking (Decryption) and Damping and AdvancedOverload (Electronics). This will flesh out your offense, improve two of your most powerful abilities, and allow you to hack [Average] difficulty objects. If you picked Lift or Barrier as a bonus talent drop a point in those, too, just to make them usable.
For the next stretch of the game you should focus on maxing out Decryption and Electronics, as Overload and Sabotage are your bread-and-butter abilities. Plus, this will allow you to hack [Hard] objects. Best of all, you’ll achieve this at rank 9 in each talent, and there’s precious little reason to keep investing in them past this point.
If you’re playing on harder difficulties, you might want to start dropping points into Pistols so you can unlock Marksman, which you’ll want just in case an enemy hits you with Sabotage. Turnabout might be fair play, but it still sucks. Since you only have one weapon talent, having your primary weapon overheat can be bad for business. After (or in lieu of, depending on difficulty) investing in Pistols, keep dropping points in Damping and Hacking. While Damping will become your third core offensive ability, AI Hacking is more situational, and unfortunately it requires quite a lot of talents to become even remotely useful. Until you unlock Advanced AI Hacking (7 ranks) you won’t be able to affect most enemies with this ability, so you should view this as the minimum effectively investment.
As your level moves into the double digits, invest in Pistols enough to unlock Basic Armor (6 ranks), after which invest three ranks in Basic Armor for Shield Boost. It’ll help shore up the Engineer’s shoddy defenses, although the merits of further investment are dubious at best - the extra damage reduction is nice, and if you boost Basic Armor up to 8 ranks you’ll end up with Advanced Shield Boost and 16% damage reduction, which is… fine, but it won’t make a tank out of you. If that’s not appealing (or at least, not immediately appealing), keep investing in Damping, Hacking, and Lift/Barrier to hit the “Advanced” abilities in those talents. Dropping four ranks into Spectre Training to unlock Unity isn’t a bad idea, either.
Eventually you’ll unlock and complete UNC: Rogue VI, which in turn unlocks your specialization. There’s only one real choice here: the Operative is just superior to the Medic, as the former gains Overload Specialization and Sabotage Specialization as compared to the latter’s Neural Shock Specialization and First Aid Specialization. When you unlock this ability, max it out as quickly as possible to empower two of your strongest attacks and gain significant cooldown bonuses for every tech ability.
Speaking of First Aid and Medicine, we’re not too keen on either of them. Neural Shock is a decent ability, but Mass Effect has a significant bias towards synthetic enemies (chiefly geth) over organic ones, and the points required to unlock an ability that has a decent stun effect and marginal damage output is a pretty hard sell. Instead, we finish off the Engineer build by unlocking the master-tier AI Hacking, Damping, Marksman and Lift/Barrier.