Here are a list of structures in the game.
Reactor
The Scrin Power Plant.
Extractor
Same as refineries but stores an indefinite amount of Ichor.
Portal
Warps only small infantry.
Warp Sphere
Makes very powerful Scrin Units and the Annihilator Tripod.
Nerve Center
Almost the same as the Nods Operation Center.
Stasis Chamber
Something that allows the deployment for Shock Troopers.
Gravity Stabilizer
Something that deploys aircraft. You better take this thing out because this thing warps in very powerful hardware which we all hate.
Technology Assembler
The High Tech center that allows many powerful units to be made and the Rift Generator superweapon.
Signal Transmitter
This thing must be taken out or a monstrous mothership will come in and cause collateral damage and a crushing blow to all foes of the Scrin.
Defense Structures
Buzzer Hive
A Hive that Buzzers live in. When infantry come near it the buzzers go out of their hives and swarm them to death.
Counters
The buzzers cant pierce even Nod Attack Bikes which armour is the weakest in the game.
Photon Cannon
A turret that can take on tanks.
Counters
Heavy tanks and infantry cause common problems but aircraft causes the worst.
Plasma Missile Battery
The Anti air version of the Photon Cannon.
Counters
Pretty powerful against aircraft but anything that drives on the ground or marches on the ground might create trouble for it.
Storm Column
This is the most expensive and the most powerful of all base defenses in the game. It can take on a variety of targets and its Ion Storm can power all vehicles that flies.
Counters
Destroy the Reactors that power it. Its weapon cause great damage to all targets and mammoth tanks nor avatars cant take this thing one on one but also swarming it with infantry is another option because its weapon does not cause splash damage. Artillery or any kind even Beam Cannons are also an option.
Growth Accelerator
This thing is quite useful when you are in dept.
Rift Generator
A superweapon and the grand finale of the Scrin. Cant destroy things that are heavy armoured.