Weedkiller

You can attempt this achievement near the start of Chapter 14, titled "Everything Has its Place."

After you grab the Lab Key from your crew in the Rosetta lab, you'll need to explore the Biology Sector. Follow your suit locator until you enter a door.

Directly in front of you, you'll see a cyst. There are a total of five cysts in this room. Your goal is to run through this area without killing any of them, saving them for the poison gas.

The first cyst is right in front of you. Use stasis on it and run past.

Turn around and use kinesis to grab the projectile it shoots into the air. Be careful not to let it drop back down, as it will kill the cyst. Fire the projectile off somewhere safe.

Repeat this process for the next cyst on the ground.

The third cyst is on the wall to your left. Use stasis on it and run by.

The fourth cyst is on the floor again. Repeat the same steps you used for the first two cysts.

The final cyst is on the wall just around the corner. Use stasis and run past it.

After you've bypassed all five cysts, you'll need to proceed downstairs. Take the lift down.

Kill the enemies that appear in this lower area.

Complete the mini-game to activate the control room and the elevator.

Return back upstairs.

Kill the enemy waiting for you there.

Enter the small glass room and use the computer console inside to release the poison gas.

This gas will kill all five cysts simultaneously, and the achievement/trophy should unlock.