These are some good strategies to try when using GDI as your race.
Bloodhounds and Orcas quick attack
*Build Refinery
*Build Power Plant
*Build Command Post
*Build Airfield (build 3 Orcas)
At this point you should use the Radar scan and the Bloodhounds to drop 2 APCs and 2 Pitbulls close to, but out of site and range of the enemies base. Move your Orcas towards the enemies base. Attack the enemies harvestors. Note that the 3 Orcas will be able to take out one full power harvester. While this attack is going on, make sure you get more refineries and a war factory up quickly. The key to this strat is to halt the enemies economy enough to get your own economy and base ahead of theirs. Also, keep using the Orcas to harass until the enemy gets Anti-Air units or defences built. A good idea is to hit the enemies expansion with the second trip from the Orcas if an obvious expansion spot exists. Be careful if you decide to use this against scrin since their base vehicle (the seeker) has anti-air capability.
Quick Economy and Tank Spam tactic
*Build Crane
*Build Refinery
*Build Power Plant
*Build Refinery
*Build War Factory
*Build Power Plant
*Build Refinery
*Build War Factory
If their is an expansion area, build a refinery or two and a warfactory at the expansion. At this point, you are going to want to continue with a few more refineries and another warfactory or two. You are also going to want to start cranking out medium tanks with a few APCs and Pitbulls mixed in to help against any enemy infantry or air units. The key to this strat is map control along with defending your own base well. If you can control the areas around your own expansion tiberium along with the area that the enemy needs to go for expansion tiberium, you will be able to outproduce the enemy and eventually win.
Pitbull harrassment tactic
*Build Crane
*Build Refinery
*Build Power Plant
*Build Refinery
*Build War Factory (Crank out 5-6 Pitbulls and a few harvestors)
*Build Power Plant
*Build Refinery
*Build War Factory
As soon as you get the 5 or 6 pitbulls, you are going to want to use them to harass the enemies harvesters. Also, pitbulls can dodge scorpion and medium tank fire, so keep them moving. While he is worrying about your pitbull harassment, make sure you are building up your economy and cranking out tanks with a few pitbulls mixed in. The key to this strat is micro-managing your pitbulls well. For this to be effective, you are going to have to take out a few harvesters and stunt your enemies economy while yours is growing quickly.
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