Engineers have the Incinerate and Combat Drone abilities and are very dangerous on harder difficulties, due to their negligible cooldown, often decimating squads if a player has been forced out of cover. They also tend to use their Combat Drones less often on easier modes. On Hardcore, and particularly Insanity, these adversaries will try to keep a drone up as much as possible.
Engineers prefer to stay as far away from Shepard (or whichever squad member has their attention) as possible, and only break cover to fire their tech powers.
- Engineers are generally a quick kill if squad powers are focused properly. Overload and Disruptor Ammo will quickly dispatch their shields and their low health leaves little room for recovery. Sniper Rifles and Heavy Weapons are very effective at taking out Engineers from a distance on any difficulty.
- The Flashbang Grenade loyalty power is very useful in rendering an Engineer useless for a few moments, even more so if they are unprotected when the grenade goes off.
- Sniper rifles will allow the player to safely dispatch an Engineer, since most of their powers are effective at medium range, giving you time to see them coming.
If playing as a Vanguard, the player may be able to quickly overwhelm an Engineer with Biotic Charge, but as always with this skill, it's a big risk. In the end, Engineers will be defeated by focused fire and proper use of abilities.