Kanes Wrath

GDI is often regarded as having very weak anti-air defenses, lacking the power of Nod's Tiberium Core Missiles or the Scrin's Shard Launchers. However, between Firehawks, Pitbulls and Slingshots, they have the ability to counter any air threat cost-effectively and easily. The key is knowing which units to use against different aircraft. This guide will explain the strengths and weaknesses of the various anti-air choices available to the GDI factions, and then cover the best choice against any particular air threat.

Anti-air defenses

Pitbull

Pitbulls are fast tier 1 scout units with a strong anti-air rocket attack. They are lightly armored, and their damage is done in barrages rather than continuously (like the Slingshot or AA Battery). Available at tier 1 and cheap to produce, they are a standard anti-air unit due to their versatility; when not holding off enemy air units, they can harass enemy Harvesters or provide light support against your opponent's ground force. It is worth noting that Pitbulls deal 150% damage against air, that is 200 rocket damage against ground and 300 rocket damage against air targets per missile.

Armored Personnel Carrier

First available at tier 1, the APC is not particularly strong against air threats, but it is relatively cheap and effective against ground targets. As a result, it is best not included as your army's anti-air support, but rather used as a unit which can fend for itself if attacked by air units, as well as provide strong anti-air when combined with several other units. Garrisoning Missile Squads greatly increases its anti-air capability, though care must be taken to evacuate the Missile Squad before the APC is destroyed in order to avoid losing the infantry and APC at the same time.

Slingshot

Slingshots are even faster than Pitbulls and are dedicated anti-air units which fire a constant stream of bullets dealing a high steady rate of damage. They have heavier armor than Pitbulls, but they will die very quickly to anti-vehicle fire, in particular cannon damage. This means that Vertigos can destroy them in one hit, so avoid clumping Slingshots against vNod or Marked of Kane. Available at tier 2, these are much less common than Pitbulls due to their specific anti-air role, although they can be used in some situations as a shock unit versus infantry, forcing them to scatter while your other units clean up the manspam.

Firehawk

Firehawks are extremely potent anti-air units that GDI acquires at tier 3. With the Stratofighter Boosters upgrade they can arrive at any location on the map quickly to counter any air threat, provided they are carrying a payload of AA missiles rather than bombs. They do extremely high damage in a short period of time (1000 rocket damage per missile), however, once their payload of four missiles (six with the Hardpoints upgrade) is exhausted, they must return to base and reload. In most cases, Firehawks are the strongest answer to air threats. However, as Firehawks are often loaded with bombs for the purpose of levelling the enemy base, they must have advance warning to prepare for anti-air threats, or otherwise they will have to hasten back to an Airfield to change to an anti-air loadout.

AA Battery

The main reason many consider GDI anti-air to be weak, the AA Batteries seem like glorified pop guns (without the Tungsten Shells upgrade), with even the lightly armored Orca able to shrug off several seconds of fire easily to get those extra couple of rockets off on that Harvester. Immobile, reliant on base power and with low damage output, the batteries are generally only useful because they can be placed at a pinch and use a separate build queue from your other anti-air units, making it easier to respond quickly to an air threat you were under-prepared to face. AA Batteries are available at tier 2.

Missile Squad

For a tier 1 unit, Missile Squads have high damage output for their cost, which is balanced by their lack of speed and vulnerability as infantry. This makes them useful for defending a particular location against anti-armor air threats such as Orcas, but their lack of mobility means it will be difficult to defend an entire base with them. The main reason they are useful is because they are a solid unit against both vehicles and aircraft when massed. Because they are infantry, they can also provide anti-air support from within garrisons or Foxholes to create stationary air defense, or inside Hammerheads and APCs to give them extra mobility. Steel Talons can also make use of Heavy Harvester, MRT, and Behemoth garrison slots to add reasonable anti-air capabilities to these units. Note that Missile Squads have a 75% damage scalar versus aircraft, making them less effective in this role than they are against tanks; that is, each missile deals 250 rocket damage against ground and 187.5 against air targets.

Mammoth Tank, Rocket Harvester, Battle Base, and Zone Raider

Included for completeness, these units have token anti-air at best. Their AA rockets will fend off very light anti-air threats but will by no means protect them cost-effectively from air units which counter them, such as Orcas or Venoms, respectively.

Supersonic Air Attack

The final tier 4 option available to GDI factions, the Supersonic Air Attack costs 2000 credits and deals high damage to all air units in a large area. Highly effective against large hordes of weak air units such as Venoms or Hammerheads, and also very useful for destroying air units as they take off or land at the Airfield. Less effective against Scrin capital ships, which can survive the strike, and, if located in an ion storm will rapidly recover from the damage.