Competitive StarCraft 2 starts out like boot camp. Every player who begins playing online will inevitably lose 15-20 matches in a row before ever coming away with a victory. But here's a way Terrans can beat Protoss in a few short minutes.
Beginners don’t usually have the skill yet to pull off timing-based frontal assaults and you certainly don’t want to square off against a Protoss player in the late game once they’ve got Colossus and High Templar on the field. So you’re going to need surprise and trickery on your side during the mid-game to beat likely-superior opponents.
The specifics for this build aren’t as important as the big ideas it’s based on: get a Reaper quickly, use it to distract and contain the Protoss, get a second base, tech up to Medivacs while getting a bunch of marines, and then use those to attack in two places at once. In practice, it looks a little something like this:
10 – Supply Depot
12 – Barracks
12 – Refinery
15 – Reaper
16 – Orbital Command
17 – @100% Reaper, start Tech Lab on Barracks
17 – @400 Mins, start 2nd Command Center
18 – Supply Depot
19 – 2nd and 3rd Barracks
20 – Bunker
@100% Tech lab, start Stimpack Research
@100 Gas, start Factory and 2nd Refinery
@100% Factory, start Starport, Reactor on Factory, and 3rd/4th Refinery
@100% Starport, swap off onto Factory’s Reactor, start more Barracks, and start double Medivac production
(Build modified from 1rax FE into 2 Medivac Timing at Gosubuilds)
Note: if the Protoss doesn’t seem to be interested in expanding before 5 minutes, abort this strategy and build way too many bunkers in front of your natural expansion. It’s best to overreact since Protoss one-base pushes are obscenely strong. Seriously. Like five or six bunkers.
Once you have your two Medivacs, load them up with as many marines as possible and send each one off to different sides of the enemy’s base. One Medivac will attack the mineral line in the main base, the other will go after their expansion. Don’t forget to continue making units during the attack.
In all likelihood, the Protoss will have their army stationed next to the ramp at their natural expansion so attack the main base first. The purpose isn’t to do huge damage, but to force the Protoss to pull their army into the main base and to strain their multitasking abilities. If you’re lucky, they’ll pull their entire army into the main, giving you free reign to attack their expansion with your second Medivac.
In game it will look sort of like the video above (just try to do a better job of keeping your units alive than this player.) You also probably don’t want to announce your presence as the player in the video does. At the lower levels of play, total surprise is the better strategy.
This is kind of a dirty trick because most Protosses in lower leagues won’t notice the second attack. They’ll get the notification that their probes are under attack, but may not hear it over the calamity of the battle in the main base. Sometimes, they’ll hear the notification, but will think it refers to the probes in the main. Even if they do respond quickly, the damage that eight stimmed marines can do to a mineral line is borderline diabolical, and you’re likely to do heavy damage anyway.
Make sure not to lose your first Medivac in the main base though. Get out of there at the first sign of trouble, you don’t want to lose those forces. They’re just a distraction.
When the Protoss sends their army down to the natural expansion to deal with your second drop, just bring your first Medivac back in for another attack. This is difficult to defend against, and most inexperienced Protoss players will fall to pieces as you bounce in and out of their bases.
You’ll almost certainly do huge damage to their economy, and it’s often enough to make the Protoss player submit to an early GG (about 11 minutes in accelerated StarCraft game time, or 7-8 minutes real world time.)
If they don’t, just try to lose as few units as possible during the drop. Retreat, and combine all of your forces (roughly 4-6 Medivacs and 30-35 Marines and Marauders at this point) for a frontal attack against the weakened enemy while expanding to a third base, adding a billion more Barracks, and going into double-upgrades. This should be the killing blow, but if it doesn’t then you’ll be in a great position for the rest of the game.