User blog comment:Necron Jesus/The Combine Overwatch(Half-Life 2) vs The Aliens/ADVENT(XCOM 2)/@comment-3189283-20180511144728

Let's see shall we

Standard Unit

While both fire powerful armour piercing projectiles, the Pulse Rifle has 30 rounds while the Magnetic Rifle only has four so it obviously gets the edge. The grenades are pretty much identical so Combine wins because of their vastly more practical firearm.

Edge: Combine Overwatch

Melee Unit

The Shock Lance looks to have the greater reach and they are also much nimbler and quicker than their counterparts. On top of that they are also an actual military unit, not just some random civilians like the Civil Protection. The greater fire rate and larger magazine of the SMG would give the Combine the edge over the Magnetic Rifle but seeing as how neither really use their firearms the superior melee option of the Aliens give them the advantage.

Edge: Aliens 

Captains

This ends up pretty much exactly the same as the Standard Unit category, with the Pulse Rifle easily dominating the smaller magazine of the Magnetic Rifle. If that wasn't enough of an advantage though the Elite Soliders can also use the Dark Energy attack which makes their offence even more potent. Marking off targets for your teammates is a fine ability but it's not directly lethal.

Edge: Combine Overwatch

TBC