Complete the 1st mission Club Hopper- Story related and cannot be missed
Survive the party at the club


Complete the 2nd mission Exit Strategy- Story related and cannot be missed
Escape from C-Block


Complete the 3rd mission You Have My Sympathies- Story related and cannot be missed
Help Van Zandt


Complete the 4th mission Regicide- Story related and cannot be missed
Defeat the Matriarch


Complete the 5th mission I Will Never Leave You- Story related and cannot be missed
Locate Tequila


Complete the 6th mission That's a Promise- Story related and cannot be missed
Get Tequila to surgery


Complete the 7th mission One Big Bug- Story related and cannot be missed
Defeat the Praetorian


Complete the 8th mission Get To The Chopper- Story related and cannot be missed
Recover Weyland's datapad

Complete the 1st mission Come to Mama- Story related and cannot be missed
Liberate the Matriarch


Complete the 2nd mission Breaking Quarantine- Story related and cannot be missed
Escape from the Research Lab


Complete the 3rd mission Grunt Hunt- Story related and cannot be missed
Wipe Out All The Marines In The Colony


Complete the 4th mission Under Pressure- Story related and cannot be missed
Solve The Riddle Of The Ruins


Complete the 5th mission Alien Vs Predator- Story related and cannot be missed
Create A New Species


Grim Reaper- You need to harvest all the available Civilians during the Campaign to get this Achievement

Mission 1 Research Lab- Once you freed your other Alien you will enter the buildings hallways with two floors. There you will notice a civilian on the top level in a closed room. This one can't be harvested and doesn't count towards the achievement.

Mission 2 Colony: 3 Civilians
After climbing up the ventilation shaft and exiting the sewers, you will encounter a Marine with a motion tracker and a civilian who escapes to the next room, If you force the door open he will shoot himself. Carefully proceed through the hallway and enter the vent above the obstacles and slowly enter the room then harvest the Civilian.

Mission 3 Refinery: 8 Civilians
After you enter the first room with Marines, you will pry open a door, There are two civilians inside both will run away, one to the left and the other through a corridor, to a room in front of you. The one running to the left is going for the elevator and call for help. And two Marines come to the rescue. Harvest him last!

The other civilian runs through a corridor to a room to grab a gun to shoot himself get him first, just sprint right after him and harvest the guy. Next you can take out the Marines and concentrate on the other civilian.

Mission 4 Jungle: 4 Civilians
After you've been ambushed in a closed off room, You will have to open the gateway to the Hive, On the top level next to the switch is a civilian, If you try to go near him he will turn around and use a grenade to kill himself before you reach him. So after you enter the room, cling to the wall or ceiling, ambush him and quickly harvest him

Mission 5: 7 Civilians
The First Civilian is straight ahead and one level down next to an android.
The Second Civilian is on top of the middle pyramid next to an android but be careful as the civilian might kill himself by falling off the the edge.
The Third Civilian is next to a pressure plate being guarded by an android. Kill the android by surprise and do not walk on the pressure plate or you might burn the civilian.
The Fourth Civilian is on the opposite site of the first one but alone.
The Fifth Civilian is walking around standing behind the wall of the fourth.
The Sixth and Seventh Civilian are inside the closed off pyramid.

Sometimes the Civilians can try to kill themselves or disappear which means you will have to restart the level so try and harvest them as fast as possible, Most of them are in the open apart from a few.

Complete the 1st mission It Uses The Jungle- Story related and cannot be missed
Find A Way Through Gateway


Complete the 2nd mission Fallen Comrade- Story related and cannot be missed
Find The Youngbloods in the Jungle


Complete the 3rd mission Matter Of Honor- Story related and cannot be missed
Discover The Elite Predator's fate


Complete the 4th mission Eyes Of The Demon- Story related and cannot be missed
Retrieve The Ancient Mask


Complete the 5th mission World Of Hurt- Story related and cannot be missed
Survive trial by combat


Complete the 6th mission Breaking And Entering- Story related and cannot be missed
Find a way into the research lab


Complete the 7th mission Reclaimer- Story related and cannot be missed
Retrieve The Second Artifact


Complete the 8th mission Extinction Agenda- Story related and cannot be missed
Destroy The Abomination

Stay Frosty- Complete The Marine Campaign On Hard Difficulty



I Love The Corps!- Complete the Marine Campaign On Nightmare Difficulty
No Checkpoints meaning if you die you will have to restart the level from the beginning

Probably the hardest out of the 3 and the most annoying

1st mission isn't too hard on nightmare, only parts that are challenging is the club part and the marine facility camp part where you have to wait for the elevator to arrive. For the club mission just run around and take shots at the Xeno's s you also have some grenades but make sure you use them from distance at close range you will kill yourself with it. Second challenging part is when your with the other marines and get ambushed by Xeno's you will have to wait for the lift to arrive takes about 20-30 seconds just around until the doors open and run straight into it.

2nd mission refinery is quite difficult and you will have to play it smart, Try not to shoot the Xeno in the head if its close to you cause it will explode and hit you with the acid and do severe damage in some cases you might even die. Once you get to the part where Van Zandt is captured and there is flamethrower right next to him. I do not recommend using the flamethrower because if you use it on the Xeno's they will chase you while on fire and explode that will kill you instantly.

Final part where you have to kill the Queen make sure you kill all the eggs first, Once Tequila asks you to press the lever to kill the Queen make sure to keep a big distance between you and the Xeno's before you press the lever because if they are right next to you while you are pressing the lever they can kill you before the cut-scene begins and then you'll have to restart the entire level.

3rd mission Jungle is not as difficult in fact the easiest once you get to the stairs pick up the sniper and scope down the alien's you can scout to see where they are and 1 shot them. Slightly hard part is the 4 androids at the end, It takes about 4-5 shots from the sniper to kill them. First is on the floor pretending its dead snipe him down with a few shots then open the door and there are 3 more fire a shot to get their attention and run back and snipe them down as they run foward.

4th mission is the same as the 2nd difficult the first part once you get to the 2 marines and pick up the smart gun make sure not to spam all of it let them get a bit close and pop em, you will have to make you way up to the ship with the smart gun once you hear the marine say "need any help" run straight into the building and Xeno's will stop chasing you.

Predator fight it easy expect when he comes down to lunge attack you, Block it and shoot him until he retreats reload and hopefully you will be able to kill him. Once you enter the hive like cave you can use your sniper to spot the aliens on the walls and kill them, Once you rescue Tequila you will return back to the arena and be ambushed by 8-10 aliens you can just run around until Tequila takes them down since she can't die or you can try kill some of them yourself.

5th mission is not too difficult until the end part where you have to fight the Praetorian, After you you meet with Katya and head outside let the Xeno's and Android's kill each other that way there will be less enemies for you to deal with. After this there is a few more Android enemies as you proceed just stand back and kill them with your sniper one by one. Once your outside there will be a few Xeno's to take care of before you meet the Praetorian.

For the Praetorian fight hit him with the grenades you picked up and run around towards the platform where you are supposed to go, the Xeno's should not follow you in there hopefully now you can use the sniper to kill the Praetorian but watch for the acid attacks.

Final Mission as you get to the open rearm the Turret and then you will be attacked by about 20-30 Xeno's just run around and let the Turret kill them but also get some shots yourself to make it faster once that is done you will be attacked by 2 Praetorians run back to the lift, here they won't be able to see you and the Turret will kill them but if you have extra ammo on the sniper use it because the 2nd Praetorian can spawn a few Xeno warriors.

After that pick up the Smart gun and all of its ammo once you get to the next part there will be a cutscene quickly run towards the side because the Android will instantly kill you if your too slow. Now equip the smart gun as the Pistol will be originally equipped after the cutscene. Now take down the Androids one by one.

Now you will have to fight Bishop himself if you picked up the 4 grenades earlier from the previous area you can bring his health to about half and the rest you will have to just keep shooting him once you beat him and pick up the data pad Bishop will attack you from behind you will have to shoot him in the head to complete the game.



I Admire Its Purity- Complete The Alien Campaign On Hard Difficulty



Magnificent, Isn't It?- Complete The Alien Campaign On Nightmare Difficulty
No Checkpoints meaning if you die you will have to restart the level from the beginning

On nightmare enemies do more damage and can kill you with 2-3 shots and there are no Checkpoints if you die you will have to restart the entire chapter from the beginning. However on nightmare Alien Campaign is the easiest of the 3 at least for me, If you take damage just run up a vent and wait for your health to recover.

Do not try to attack 2-3 marines at the same time cause you will die fast. Lure them with your hiss and take them down one at a time, On certain parts you can skip the enemies and just run past them.

In the Final fight with the predators use the heavy attack and keep spamming it continuously the predators will be unable to do anything and basically be stunned and once that fight ends you should unlock the achievement.



It Ain't No Man- Complete The Predator Campaign On Hard Difficulty



One Ugly Mother- Complete The Predator Campaign On Nightmare Difficulty
No Checkpoints meaning if you die you will have to restart the level from the beginning

Slightly more challenging than the Alien campaign as you don't have the smart disc and combi Stick for the first 2 chapters, Xeno's do more damage and you cannot block there heavy attacks. Marine's are easy to deal with as long as you get them one at a time.

Once you get the smart disc and combi stick you can just run around and spam them and with that taking down the Xeno's and the Android enemies becomes much easier.

During the Praetorian fight climb the tall pillars and spam the smart disc, It cannot climb walls and will just stand there. However Praetorian does shoot the acid attacks so just dodge them by jumping on the other pillar. The Xeno minions for some reason cannot reach you as long as your standing in the middle, If you move towards the ledge they might land a hit.

The final fight is actually easy once the Predalien loses slight amount of health it will start to shake the arena, at this point jump to the corner part of the arena and plant the Mines. You can plant about 4-5 with the amount of energy you have, just wait for the Predalien to come to you it will take damage and run away then you repeat the process until you beat it, takes about 3-4 turns to kill him with this technique.


Game Over, Man!- Complete All Three Campaigns
Complete all three campaigns on any difficulty to get this Achievement

Marine

I Like to Keep This Handy- Kill 2 enemies with one shot with the Shotgun
Might Occur naturally through the Campaign but can also be achieved in Multiplayer.

Let's Rock!- Kill 5 enemies with one burst from the Smartgun
Mission 4 is where you can try and earn this as you will have to use the smartgun in that scenario because of the swarm of Xeno's coming towards you otherwise the this achievement can also be achieved in Multiplayer.

Elite Sniper-Kill 10 enemies with head shots from the Scoped Rifle
Will naturally come through the Campaign otherwise can also be achieved in Multiplayer.

Gunslinger- Kill 30 enemies with the Pistol
Will naturally come through the Campaign as Pistol is your default weapon and you always have it, otherwise can also be achieved in Multiplayer.


Predator
Spin Doctor- Kill 2 enemies with one throw of the Smart/Battle Disc
Will naturally come through the Predator Campaign otherwise can also be achieved in Multiplayer.

Stick Around- Kill 20 enemies with the Combi Stick
Will naturally come through the Predator Campaign otherwise can also be achieved in Multiplayer.

Collectables
Harsh Language- Discover all 67 Audio Diaries
There are 67 Audio Diaries to collect in the Marine Campaign most of them are right in front of you, Other might be hidden around corners or bushes make sure you check them they are not too hard to find.

Quite a Specimen- Destroy all 50 Royal Jelly Containers
There are 50 Royal Jelly Containers in the Alien Campaign most of them will be in the vents or even wall areas, some might be on the floor right next to you so make sure to look around and explore a little bit.

Fortune and Glory- Find all 45 Predator Trophy Belts
There are 45 Trophy Belts in the Predator Campaign and once again most of them are in plain sight some are on trees and bushes in open areas and some might be behind corners make sure to take you time and check the entire area.