Command & Conquer/GDI units

Minigunner
The basic GDI infantry unit, cheap and quick to train but weak by themselves. They are best used en masse to overwhelm other enemy troops. They are most effective against similar enemy infantry and light vehicles, but should not go up against heavy vehicles without some strong backup, nor should they take on enemy infantry such as flame troopers.
 * Cost: 100

Grenadier
Faster and slightly more expensive to produce than the minigunner, but they pack more of a punch. Unlike the minigunner, grenadiers should not swarm the enemy in close bunches, as their grenades can do devastating damage to themselves and their GDI allies. Space them out when defending against infantry and use them carefully against enemy vehicles. They can also launch up hills and over walls.
 * Cost: 160

Bazooka Infantry
A very powerful infantry unit, but they move slowly and aren't cheap. Excellent for use against enemy vehicles and buildings when they are in large numbers, but their slow movement means they can get crushed by tanks if they don't get out of the way. They can fire against air targets, but are not too effective against infantry.
 * Cost: 300

Engineer
Almost completely defenceless, but an important unit in the game. Used to capture enemy buildings, just make sure they have a good escort to protect them on their way, or place them inside armoured personnel carriers.
 * Cost: 500

Commando
Able to take out any enemy infantry with a single shot and from a good distance. They also carry C4 to destroy buildings, but they can take damage very quickly. Completely ineffectual against enemy vehicles, so they shouldn't go anywhere near them. You can't produce your own commandos, instead you are given one by GDI for the occasional mission.
 * Cost: 1000

This unit can only be built in multiplayer games.

Vehicles
GDI Vehicles are the most strongest and the most violent things you will ever see.

Humm Vee
A lightly armoured but very fast vehicle. Best used for scouting out the surrounding area, it's not too good in battle by itself and shouldn't take on other enemy vehicles especially the Light Tank.
 * Cost: 400
 * Speed: Fast
 * Armor: Light
 * Weapon: Machine Guns

Additional Notes

As a low tech unit, M998 High Mobility Multipurpose Wheeled Vehicles, commonly called Humvees, traced their lineage to before Tiberium was discovered on earth, and entered the First Tiberium War with little change to their basic design. Basically, Humvees were fully enclosed units with reinforced windows and a powerful engine, and they were armed with a roof mounted 7.62 mm M-60 machine guns.

Humvees were used in the first Tiberium War by the GDI, and featured an M-60 Machine gun for use against infantry targets. The M-60 was highly ineffective against armored targets, although against structures it could could be massed. A large group of Humvees would slowly wear down a structure's armor. Although not as fast as the Nod Buggy, Humvees made up for it with heavier armor, while still being reasonably fast and were able to take out large numbers of buggies. The heavier armor made for a more expensive unit overall. Unfortunately, the armor was not heavy enough to sustain tank bombardment. Generally, Humvees were used as light recon units and anti-infantry support, although they could also be used as escorts for APCs if necessary. As an extremely low-tech unit, humvees were deployed with most GDI task forces during the First Tiberium War. GDI commanders used them against most Nod light infantry in skirmishes.

Nod's Obelisk of Light, as a powerful one hit strike, was sufficient to destroy a Humvee in a single shot. Rocket Bikes were also suited for attacking them, being fast enough to catch a Humvee, and having anti-armor rockets, but their lack of armor meant that the M60 machine gun was often a more than effective counter to this approach. Light tanks could certainly do the job, but were too slow to catch Humvees and destroy them. Flame tanks, owing to their combination of relatively low speed and short range weaponry, were generally not used against Humvees, and in any case would be highly ineffective.

The Humvees were phased out and latter on replaced with Wolverine walkers for recon and anti-infantry roles. And new Pitbull ATVs fullfilling the Humvees' non-combat roles, though not used on the front lines. A number of these vehicles continued to be used even as far as 2047, but were mostly a curiosity rather than a fully fledged utility vehicle.

APC
The M113 APC carries 5 infantry but also can shoot machine guns. IF the vehicle is destroyed while carrying infantry the infantry will bail out. Use APCs to protect the Infnatry from danger or for ambushing like load APC with Bazooka Troopers and when a light tank destroys it the Bazooka Men will Surprise it.
 * Armour Medium
 * Weapon Machine Gun
 * Cost 700
 * Speed Medium

Additional Notes

Given their reliance on infantry (at least more than the Soviets), the Allied Forces were the creators of the APC. The vehicle was small, heavily armoured and fast. Mounting a small machine gun, it was effective against infantry and it's speed and ability to crush infantry made it highly effective against soldiers of all types - with the exception of the shock trooper, whose armoured suit prevented him from being crushed. However, the machine gun was still effective against these targets. Although it could be used to transport engineers, the number of engineers required to capture most buildings meant that this was often not an effective tactic. The Allied phase transport was built around an M113 chassis.

During the First Tiberium War, GDI used the APC. It was essentially the same APC that the Allies had used, with very few differences. However, owing to the different nature of that conflict, the APC accordingly had a different role. Although powerful against infantry and able to crush all types, the ability of the Engineer to capture full strength buildings meant that the APC could be used to transport Engineers into fortified Nod bases and have him capture enemy buildings, putting them to good use for the GDI.

Armoured personnel carriers could also be used as scouts, owing to their speed and their ability to absorb more damage than could the fragile Humvees. One important feature that the APC provided was the ability for infantry to cross Tiberium fields without damage.

Medium Tank
The M1A1 Abrams Tank is more powerful than the Nod Light tank but slower.
 * Cost 800
 * weapon single 120 SABOT cannon
 * Armour Better than the Light Tanks armour
 * Speed Medium

Additional Notes

The M1 Abrams Medium Tank was a heavily armoured tracked battle vehicle, first produced by the Allied nations during Great World War Two which formed the backbone of the Allied and later GDI armoured divisions. It's single 120mm cannon allowed it to be a match to enemy armour, while one 7.62mm machine gun and a Browning M2 .50 caliber machine gun with another 50 caliber coaxial machine gun mounted next to the barrel allowed it to counter enemy infantry to a degree, while retaining it's maneuverability. Also, it cost less to produce than heavy Soviet units or more sophisticated designs of the Brotherhood.

The medium tank was first designed and fielded during the Great World War II to match the amounts of Soviet armor. Although the lightest tank of the USSR was still stronger, it did even the odds somewhat in that the medium tank could be far better mass produced than any Soviet tank, as it was significantly cheaper. Unfortunately, it was outclassed by the T-80. The heavy tank was as fast as it, but mounted two 105 mm Cannons, and therefore, almost twice the firepower.

The design of the tank proved so successful, that during the First Tiberium War its upgraded versions were GDI's main battle tanks. The GDI medium tank could defeat any Nod vehicle in a one on one fight.

As a counter, rocket infantry squads were effective, although their lack of speed meant it could be difficult for a target to not be squished by a medium tank - care was needed. Furthermore, medium tanks could be targeted by recon bikes or Bradley M2s in groups, at which point an Abrams would fail, same as in a situation in which a gunship (such as the Mi-24 Hind) would attack it. But in general, it was highly effective against enemy armored vehicles, and was a match for a flame tank one-on-one.

The M1 Abrams were eventually phased out and replaced with Titan Medium Walkers and Predator MBTs.

Rocket Launcher
The M270 Missile launcher artillery is good against infantry and Aircraft. Not good for Obelisk Guard Towers.
 * Cost ????
 * Armour weak
 * Weapon Multi Missile launcher
 * Speed Slow

Additional Notes

The Mobile Rocket Launch System was the GDI’s main artillery unit during the First Tiberian War. Based on the United States M270 Multiple Launch Rocket System, the GDI’s MLRS units delivered multiple rocket rounds effective against infantry and vehicles, and somewhat less effectivly against aircraft.

Although it might seem reasonable that these units could fire all 12 rockets in a single volley, GDI tactics emphasized sustained fire, and it was deemed more important that these units were able to maintain fire rather than dispense immense amounts of explosives fast and become useless.

Typically, MLRS units were placed behind the lines, where their firepower could be brought to bear from long range, whilst protecting the MLRS from direct attack. Mammoth Tanks were ideal for this purpose. Few vehicular units could ignore a Mammoth Tank to go for the MLRS, whilst infantry were easily shredded by the MLRS.

However, there were weaknesses resulting from the emphasis on attack only - it was slow, lightly armored, and had a minimum range - it could not hit units or infantry that were immediately adjaicent to it. As a result, MRLS units usually moved in company with other units for protection. Nod found its attack cycle extremely effective against the MRLS - fast enough to get in within the MLRS's minimum range, and effective against its weak armor.

The M270 MLRS was replaced by the Hover MLRS following the conclusion of the First Tiberium War.

Mammoth Tank

 * Weapons 2 missile launchers and 2 cannons
 * Armour Heavy
 * Cost 1500
 * Speed Slow

The X-66 Mammoth Tank is a foe you dont want to mess with. It is slow but heavier armed with better cannons. Use it to protect weaker units like when enemy flame tanks are incoming pull the weak units back and send in the Mammoth. This unit requires a repair bay and the Weapons Factory.

Orca

 * Armour Light
 * Weapons Just Missiles
 * Speed Fast
 * Cost 1200

The Orca Assault aircraft fires missiles at its enemies but hates enemy SAM Sites.

Additional Notes

The ORCA Assault Craft was a multi-purpose support gunship of the Global Defence Initiative, employing a set of twin articulated jet engines as propulsion in place of the classic rotary wing, providing it with incredible maneuverability, but also substantially limiting endurance. These advantages came at the expense of armour, allowing the Orca to withstand only a few missile hits, provided it didn't outrun these missiles first.

The craft was armed with two weapons - a six barreled, forward mounted chaingun (equipped with a searchlight) and a pair of Dragon TOW missile launchers on its sides, each containing nine rockets. Some later models had two forward mounted machine guns.

It's compact design allowed it to fit in small passages such as canyons with ease, as well as be transported and deployed from freight trucks or specially designed resupply and transportation trucks. The fuselage dimensions limited the crew size to only a single pilot, limiting the craft's performance in combat somewhat.

While it had its drawbacks, the design proved so effective during the First Tiberium War, that it served as a basis for GDI's air forces design up to the Third Tiberium War. It was found to be particularly effective against Nod M2 Bradleys and buggies, as they had no anti aircraft capability.

Nod didn't produce these assault craft, even though they acquired the schematics, due to the engines emitting too much heat and being extremely vulnerable to IR tracking missiles.