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Base Construction is the foundation of the game because you need a base to do anything.

Base construction seems pretty straightforward, and it is. You will start out with an MCV, in the case of "Global Conquest mode" and the campaign of the game. Still, base building is separated into three branches: Tier 1, Tier 2, and Tier 3.

Note: All structure names are for GDI.

[edit] Tier 1

Tier 1 consists of basic structures to help you start off on your way. These include:

• Main Build Queue: Power Plants, Cranes , Refineies, Armouries , Barracks, and War factories.
• Defensive Structures: Watchtowers, Surveyor, Guass Cannons, and Silos.

Also in Tier 1, in your barracks/warfactories you will be able to build a handful of starting units.

[edit] Tier 2

Tier 2 is the next branch. You are considered to be in Tier 2 when you build a Commandpost. When you do this, you will unlock some new structures for building units and getting up to Tier 3. These structures include:

• Main Build Queue: Airfields and Tech Centers.
• Defensive Structures: AA Turret and Statue of Kane (Nod exclusive).

Tier 2 you will get another handful of units to help with things such as clearing garrisons and you will also get aircraft which can turn the tide of a battle. Also in Tier 2 is when you might first get upgrades for your units if you choose not to build an Armoury.

[edit] Tier 3

Tier 3 is the final branch. You are considered to be at Tier 3 when you have a Tech Center. This will unlock the rest of the units, structures, and upgrades. These structures include:

• Main Build Queue: Space Command Uplinks.
• Defensive Structures: Sonic Emitters and Ion Cannon Control Center.

This final Tier will give you much better units, including walkers which can turn the tide of a battle or destroy an enemy's base single handed. When a Tech Center is built, you will have a few more upgrades that will probably be the best, but most expensive.