Kill 5 Cysts in the Biology Building with a single poison gas cloud.
Obtained in Chapter 14
This is shortly after starting. You will get a key after meeting up with other characters and access the biology area. There are enemies called Cysts on the ground and on the walls. There are exactly 5 of them. This is the only spot you can gain this achievement. Walk in and stais #1 on the ground. Run forward and turn around to catch the bomb and throw it with kinesis. If you don't, the plant will die. If this happens you can restart your checkpoint. Do the same with #2. You will see #3 on the wall. You should stasis it, but do not worry about the bomb as it won't hurt it. Stasis #4 and grab the bomb as well. When you start getting around the corner you will see #5 on the wall. Again, just stasis and run. Go down the lift and kill the enemies. Do the puzzle to get things working again. Return up the lift, kill any enemies that attack. This is important because once you turn on the gas, the enemies will run down the hallway triggers the bombs and killing the plants. Use the computer to kill the plants with the gas, and you will unlock the achievement.
Collect all Alien Artifacts.
You will obtain this while going for all other artifacts. There are 10 total alien artifacts and you can view what chapters they are in by going to the progress menu.
for a guide containing all collectibles and side mission details.
Close Encounter 10
Kill 10 alien Necromorphs.
During the later chapters of the game, you will face a new type of Necromorph. Instead of humans, they are aliens. They are tougher and you will find it easier to stasis them and use heavy weapons. You should be able to get this by normally playing through the game, as there are plenty.