Zombie Apocalypse: Never Die Alone

Easy achievement. The first 2 levels have easy goals or objectives. If you can't do them in one playthrough, then simply play that stage again going for the next unchecked objective. I got mine in the second level. It shows you the objectives before each level, so you know what to go for. When you finish the objective in the match, a note will appear briefly in the bottom right corner noting you finished that objective.

Here are the objectives for Level 2 and how I got finished them:

Score 1,500,000 points - Keep a high combo and keep your distance from the Sheriff when he shows up.
Kill 50 enemies with the shotgun - Use Father Bill, he is the only one with a shotgun.
Get 15 Zombies Dancing - Use Def Money for this one. Wait until you get a large group of zombies and use his Bait - the Boombox.
Kill 20 Enemies with the Flying Donut - Stand next to the Flying Donut (the crane) and stay there next to it until it kills 20 zombies. Do this one before the Sheriff shows up to make it eaiser on yourself.
Kill 10 Enemies with the Street Sweeper - This one took me 2 tries to do before I got it as it's a bit tricky. The sweeper is towards the bottom of the map, but basically use the same strategy as the Flying Donut. Stand next to the sweeper and lure / guide zombies into the sweeper.

Upon completion of the last objective, the achievement will pop.