Command & Conquer 3: Tiberium Wars/Scrin Units

Infantry
Most Scrin infantry can garrison inside buildings, but those that can cannot fire out in the manner or riflemen or missile squads.

Description
Buzzers are the equivalent of GDI riflemen and Nod militants. While previous versions of the game made them inflict Gun type damage (thus, a large group of Buzzers could eliminate tanks), current versions have them inflict sniper-type damage instead.

Therefore, they are only effective against infantry. Being a large cloud of razors, the Buzzers are immune to being squished, but have low armour and no range. On the other hand, Buzzers are the fastest-producing and cheapest infantry, making it very easy to simply rush a group of infantry with them and call it a day. Their cheap cost also makes them gain veterancy quickly, but considering they are already most effective against infantry, their usefulness remains limited.

Buzzers can also clear enemy garrisons.

Although buzzers themselves can garrison inside a building, they are incapable of firing out. This is primarily a security measure to keep your fragile Buzzers protected.

Counter
Since they cause sniper-type damage, any kind of vehicle or aircraft can attack Buzzers with impunity.

Description
The Scrin response to missile troopers, Disintegrators are armed with destructive beam weapons that cause quite a lot of damage and fire very quickly. On the other hand, their range is almost equal to that of Buzzers, and as such must close the distance with enemy vehicles first to bring them down.

Their special gimmick is that they explode when crushed, causing damage to the crushing unit. A predator running over a squad of Disintegrators will often critically damage it. Unfortunately for the Scrin, Nod can equip their Scorpions with Dozer blades, making them impervious to Disintegrator explosions.

Counter
Anti-infantry weaponry will always work. Riflemen are the cheapest counter, but Grenadiers, Snipers, Shadow Teams, Commandos, and Black Hand are all viable counters. Although anti-infantry vehicles will also work, Disintegrators can easily counter.

Description
The Scrin engineer, Assimilators are equivalent to that of GDI Engineers in all respects but one - they are invisible while not moving. This special ability is extremely difficult to use properly, but it can turn the tables on a lone enemy engineer who thinks he can just grab that neutral tiberium spike and get away with it.

Being engineers, they are able to capture enemy buildings, repair your own buildings instantly, and capture neutral structures.

Counter
Being unarmed and having absolutely no defences of its own, Assimilators can be killed by any unit. Staying still is a good strategy for the Assimilator for the most part, but if the enemy wants that Assimilator dead, she or he can bring in stealth-detecting units for an easy kill.

Description
More akin to missile squads than Disintegrators, Shock Troopers also double as the heavy anti-vehicle infantry of the Scrin, making them similar in purpose to Zone Troopers. While Zone troopers pack more power, the Scrin can teleport their shock troopers short distances once upgraded with the blink packs. This allows them to teleport behind tanks, hitting them in the thin rear armour.

What separates shock troopers from the zone trooper, however, is its plasma disc upgrade. This transforms the shock trooper weapon from a pulse-firing laser to a Seeker-like plasma disc. While it provides a firepower boost, the biggest advantage now is its ability to strike air units.

Counter
Infantry and anti-infantry weapons are the way to go with Shock Troopers. They can also be crushed by Scorpion Dozer blades. APCs, Raider Buggies, and Gun Walkers also can prove effective against Shock troopers.

Description
The Mastermind is essentially an alien clone of Yuri from the Red Alert series. It can control any unit or structure via its Manipulator Device ability, putting it under your control. Its secondary abilities allow it to teleport units to its location. Therefore, if one can run a Mastermind to the back of an enemy's base, one can summon a group of Shock Troopers to that position and wreak havoc.

The Mastermind, however, remains completely unarmed aside from its manipulator device.

Essentially the Scrin's commando, only one Mastermind can be created at a time.

Counter
The counter varies on which units you are attacking it with. Anti-infantry vehicles, like APCs, are best. That way, when one gets mind controlled, it won't be able to cause considerable damage to nearby allies. Its manipulator device cannot be applied to aerial units, so the Kane's Wrath specific Hammerhead gunship is effective in an anti-Mastermind role, but be wary of its teleport ability. It can easily turn the tables against you.

Stormrider
Cost: 1500 Credits

Counter
The best way to counter the Stormrider's full attack capacity is NOT to destroy the Gravity Stabilizer it's stationed at, but to just throw whatever anti-air you got at it. You're guaranteed that your missiles can deal a ton more damage than it's pulse cannons.

Devastator Warship
Cost: 2400 Credits

Counter
The Devastator Warship is easily countered with air-based anti-air, provided that the Devastator isn't escorted.

Planetary Assault Carrier

 * Cost 3000

Counter
The Planetary Assault Carrier is easily countered by first taking down the eight sub-aircraft that it launches at you. Then while it's spawning a new replacement, hit it with your anti-air hard and fast to quickly take it down.

Mothership

 * Cost 5000

Counter
To counter the Mothership takes nothing short of a miracle (or a ton of Firehawks if you got access to them). Heavy armor, a really powerful gun, but slow as hell, making them perfect targets to throw whatever anti-air you got at them.