There are 9 achievements/trophies tied into the games combat system. These involve using stealth attacks and the array of weapons on offer kill opposition forces in specific ways and accumulating 100 kills on both human and mutant enemies.
Here’s a list of said achievements/trophies and how to accomplish each:
Description: Stealthily kill 15 Enemies.
Crouch to move silently and use shadows to sneak up behind enemies. Once you are at a close enough range a button prompt will appear on-screen prompting you to either kill or knock out the enemy. This achievement/trophy requires you to kill 15 enemies in this fashion.
Soldier & Antibiotic
Description: Kill 100 Human Enemies & Kill 100 Mutants.
This one is fairly self-explanatory. If you go in all guns blazing, you should have this unlocked by the end of the game.
If you went through all stealthy on your first playthrough and are short on the human-based kills, when you are good to go, load up some of the more enemy-filled levels: Revolution, Bandits, Contagion etc. and play through them a few times to expedite the process.
No Shooting Allowed
Description: Kill 10 enemies in a row with Throwing Knives
You can use throwing knives to one-shot kill most human enemies from a distance. After they go down, you are also able to go to the body and loot it to recover the knife. To get 10 kills in a row with knives, you will need to do so. The best place to do this is in the 'Bandits' level as there are plenty of bad guys about and it is very dark, making it much easier to sneak around than some of the other human enemy-populated levels.
Description: Kill at least one Enemy with each Weapon available in the game.
Self-explanatory. Simply pick up each weapon in the game and get a kill with each. Here is a list of the weapons required:
- Kalash 2012
- Incendiary Device
- Throwing Knife
Description: Set 2 Enemies on fire at once.
Use your incendiary devices to hit enemies and set them on fire. Note that you do not need to hit 2 enemies with the same device, you can use as many as you like. There just needs to be 2 enemies on fire at once to earn the achievement/trophy.
Description: Make 10 Spiders flip belly-up.
When you face the spiders, you will be told that they are afraid of light. If you pull out your torch and focus the beam on the spider for a few seconds it will rear up and fall on its back. Do this 10 times and the achievement/trophy will unlock.
Description: Kill 5 Shrimp with Grenades.
Simply kill 5 shrimps with grenades. This is obviously best attempted on a mission with swamp or water source that houses shrimps. these include: Sundown, Nightfall, The Crossing and The Garden.
Note that the spitting shrimp seem to be the type of enemy required to be killed via the grenades for this one to unlock as I killed plenty of the other variety without luck.
Description: Kill a Demon with the Helsing.
To do this, you need to do as described above the earliest you can do this is by purchasing the Helsing from the gun shop in the 'Quarantine' level and carrying it through the next few levels. You will encounter a couple of demons on the 'The Crossing' level so kill one with the weapon to unlock this one.