Combine Units + PLUS+ [Invasion Mode]

Combine Medic

Combine Commander

Combine Engineer

Combine Sterilizer (Incendiary Assault unit) 

Combine Shielder 

Combine Veteran

Combine Juggernaut (Heavy unit wileding pulse machine gun/minigun)

Combine Battle Drone

Combine Grenadier

Combine Wasteland Mines

Others

Combine Tripod

Combine Vindicator (enhanced & specialized commando; specialized to deal with superpower individuals or any individuals possess higher combat skills)

Combine Flametrooper

Combine Comminutor

Fly Synth

Vortigaunt Synth

Attack Synth

Combine Frigate

Combine Destroyer

Combine battlecruiser

Combine Battleship

Combine Mothership

Combine Camo-Soldier (their ability is to turn cloaking device on)

Combine Scorpion Synth

Combine Commando (More equipment, gear, and weapon with advanced combat skills)

Combine Assault Walker

Combine Raptor synth

Combine starfighter

Combine light cruiser

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Combine Warship

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