Allow no Red Faction to survive your attacks on their mountain base.


This one is missable. In the first mission, when you are flying on some vehicle, you should kill all the Red Faction guys outside of the base. This means killing everyone before you get the objective 'Infiltrate inner defenses'. Just look around carefully and watch your radar, if you see any red dots - locate and destroy the enemies. You should get the ach BEFORE you enter the base, if it doesn't pop up - you've missed someone.

Middle mouse button shoots out rockets which may help getting the guys inside buildings.

Z turns on thermal view which makes enemies easier to spot.

Clear a safe path to the Terraformer for Hale.


You get this for completing the first mission.

Rescue the pinned-down Red Faction soldiers.


This unlocks in the middle of the second mission (Tip of the Spear). The pinned Red Faction cannot die, so you will get this automatically when the enemies are dead and you move on to the next area.

Reunite Sgt. Winters with the Red Faction.


This cannot be missed, too. Unlocks in the end of the second mission.

Get 20 kills with the Shard Cannon.


That weapon can only be used in the 3rd mission. If you have difficulties in getting 20 kills throughout the mission, you may choose to reload checkpoints and kill the same enemies over and over again until you get 20 kills. It counts just like in the original game's achievements.

Wipe out the Cultist military camp.


You get it upon completing the 3rd mission.

Get 20 kills with the Sharpshooter.


You get the weapon in the fourth mission. The tactics are the same as for the Shard Cannon: you can reload a checkpoint several times and kill the same enemies, which counts for the ach, or just get 20 kills the normal way.

Eliminate 10 enemies using one of their own turrets.


Turrets can be found in the 3rd and 4th missions. Restarting checkpoints works here as well.

Kill Mallus.


This happens in the middle of the 4th mission.

End the three-way battle between yourself, the aliens, and the Cultists.


The battle takes place in the end of the 4th mission. Eliminate all the enemies to get the achivement.