Grenadier build: Heavy Gunner
Abilities: Launch Grenade, Shredder, Suppression, Holo Targeting, Chain Shot, Salvo, Saturation Fire
Gear: EXO/WAR Suit, Rocket/Blaster Launcher, Grenades
Accessories: Perception, Scope, Autoloader (Bonus: Expanded Magazine)
The Heavy Gunner provides incredible support fire capability, backed up with a respectable amount of explosive ordnance. Shredder and Chain Shot combine to wreak havoc upon robotic enemies, while Holo Targeting ensures every follow up shot from the squad gains a significant accuracy boost. Suppression keeps enemy heads down and neuters their aim, and Salvo allows you to remove enemy cover then tear them apart with a follow up shot. Its alternative, Hail of Bullets, may tempt you with its guaranteed hit chance—but by the time you reach Major, you should have enough Scopes and Perception PCS chips to make the extra accuracy redundant, while extra explosions are never unnecessary.
Rupture is a key skill that you must have on at least one soldier in your squad, but if you bring multiple Grenadiers, I recommend Saturation Fire on your Gunners. This build sacrifices explosive potential for cannon power, so the skill gives back some AoE capability while also making good use of your high aim to hit multiple enemies at once. The fact that it also applies Shredder is just icing on the cake.
Aim is critical for Heavy Gunners, as missing your Chain Shot is the difference between wiping out a Sectopod and being fodder for its angry, angry lasers. Autoloaders and Expanded Mags help to counteract the huge amount of ammo you ll burn through, and a Rocket (or later, Blaster) Launcher grants some more AoE potential to Salvo off towards your enemies.
Grenadier build: Demolitions Expert
Abilities: Launch Grenade, Blast Padding, Suppression, Heavy Ordinance, Volatile Mix, Salvo, Rupture
Gear: EXO/WAR Suit, Shredder/Shredstorm Cannon, Grenade, Acid Grenades
Accessories: Conditioning, Stock, Autoloader (Bonus: Expanded Magazine)
Typically responsible for millions in property damage, Demolitions Experts are the purest form of Grenadier. Heavy Ordinance, Volatile Mix and Salvo allow you to blow things up effectively and often, while Blast Padding allows you to take damage instead of just dishing it out. Suppression remains an effective pinning perk over the less reliable Demolition (who needs a cover destruction perk when you ve got five explosives?), and Rupture provides powerful single target damage to round out your otherwise AoE focused arsenal.
Acid Grenades and Shredder/Shredstorm Cannons are excellent picks for Demo Experts, making up their lack of Shredder with plenty of armor removal capability. Blast Padding combos well with a Conditioning PCS to make this soldier your main tank—and with the extra armor of an EXO/WAR Suit (and even a Plated Armor vest) you ll be approaching incredible levels of toughness. Autoloaders and Expanded Mags are still good to keep your suppression fire going, while a Stock makes the most of your lack of accuracy by ensuring damage regardless.
Once you pick up Rupture, consider accessorizing your Demo Experts more like their Heavy Gunner brethren—Scopes and Perception chips will make your Rupture more reliable, which will allow ridiculous damage combined with your squad and particularly with your Gunslinger.
More of our recommended XCOM 2 soldier builds: Ranger / Specialist / Sharpshooter / Hybrid builds