Sc2 matchmaking achievements
In another, you have a limited number of Protoss units, but you have to rack up as many kills as possible in just a few minutes. You have to finish a qualification round without losing any matches, and if you lose at least one match in each qualification round, you'll have to wait until the next season.
Terran players can also earn the "Just a Scratch" achievement by repairing at least 1, damage on their own and allied buildings and units.
Each one requires a slightly different action to unlock, and you won't get any reward beyond achievement points and the ability to place these achievements in your profile's showcase. You'll have to rack up literally thousands of victories in 1v1 matches to earn all the Solo League quick match achievements. This advice might sound lame, but you'll just have to keep on playing, waiting for your opponent to use the right strategy so you can earn these achievements. Fortunately, Exploration is the outlier in terms of difficulty.
Blizzard did include one achievement that is incredibly stupid and almost impossible to unlock. Turtling players can be overpowered by somebody who quickly expanded.
Jumping Into the Deep End So you've completed the single player campaign and have toyed with the idea of testing your skills online. Just like for the solo league achievements, the fastest way to rack up wins across the matchmaking achievements is to play at random.
Slogging Your Way Through Starcraft 2 Multiplayer Achievements
The number of people who don't care about achievements far outnumber the people who do, and if that's your deal, just focus on winning league games.
The very first tier of achievements start at 10 victories for each race choice Terran, Zerg, Protoss, and random.
The campaign, as in any RTS, probably did a very matchmaking achievements job of preparing you against other human players. I'm sure some Zerg players use changelings extensively, but I generally only see one or two a game, if that. You won't get credit for all the difficulties, but you can still work towards two or three at the same time. Unless you're really good at the game, some will be close to impossible to earn. These are little more than little bonuses Blizzard tossed to players, and there are only a few you can actually work towards unlocking.
You can ping the map and hope that they'll attack a specific target, but you'll never see A. It's debatable whether or not achievements are an inherently "good" thing to have in games, but they're here to stay.
Basically, you pick them up as you use the basic matchmaking functionality and win matches. From personal experience, there's less balance in these matches.