Well, this is a GoSu Starcraft player, so listen up. First, don't put all your resources into rushing, make a "tech tree"(ie. Protoss, make a Cybernetics Core before you zealot rush, Terran, make a Factory(be sure to wait for medics and firebats before you attack) and Zerg, make a lair) If you lose most of your attach force, don't send in two more if the terran enemy has 20 tanks behind a wall, its pointless. Instead, make units like high templars to counter them. Most people don't think to do this, but use the stasis field on enemy units to put the out of the way for a while, then put units around them to kill them as soon as they come out.

Playing on a map with water? Can't get into the enemys base because they have a inpentrable defense? Well, look no farther then your own tanks. Siege across the water to kill the turrets, then have dropships with marines, firebats, medics, goliaths and tanks waiting to drop in. Don't refrain from dropping a few vultures with spider mines into you enemys gathers, you can take them all out. If their terran and lift, have air units ready to punnish them.

Feel like attacking from the front? Use a force of a few gaurdieans on the back to draw their forces back, then attack from the front. Don't attack when you have your 24 lings, wait until you have fully upgraded lings and hydralisks to attack. Be sure to attack in the proper order, like melee units before range unitsm depending, of course, on the defense you are facing.

IMPORTANT- In games with more then one enemy, be sure to leave a sizable defense at your own base, because smart players will, instead of saving their ally, go for the leading attacker's base. Oops, you just sent out your 60 guys and have NO defense. Well, any good player as your enemy and you can kiss your ass goodbye, because put your head between your knees, because your going down.
One last thing. You see people with 12 factories, and you want to do that too. DO NOT make more producing building then you can handel, because you will have 100 minerals and 12 factories, not a good position.
If you ever want to play on Battle.net? with me, come to channel Clan i[D] and ask for GreatBob[iD]. I hope this helps, and remember, you can't become good overnight, you must play for a long time to learn everything.
Good Luck on all future Battle.net? Indevers.
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