Guide to Combat Engineer

From Colonial Marines Wiki

Combat Engineer Guide

Tools of the Trade

Image Name Function
Screwdriver.png Screwdriver Used for securing and unsecuring sentries, Also used to hack doors.
Welder.gif Welding Tool Used for cutting through walls and fixing sentries. Has 20 units of fuel inside.
Crowbar.png Crowbar Used for Opening unpowered doors and displacing girders so you can move them.
Wrench.png Wrench Used for securing most objects to the ground including girders,vendors, also has another use to rotate sentries. Easily the most used tool in your arsenal.
CableCoils.png Cable coil Used for fixing robotics and diverting power to other areas.
Multitool.png Multitool Used to hack doors/ vendors along with disabling mines.
Wirecutters.png Wirecutter Used for cutting cable coil and mending it.

Materials of the Trade

Image Name Function
Metal.png Metal Used for primarily making tables and walls/false walls.
Plasteel.png Plasteel Used for building sentries and setting up barricades.
Glass.png Glass Used for making directional or full tile windows along with reinforced glass when rods are applied.
Planks.png Wooden Planks Used for creating tables and a wooden barricade to provide temporary safety.
Rods.png Rods Used to make reinforced tables when applied to a standard table and reinforced glass, can also make grilles solely with rods.
ReinforcedGlass.png Reinforced glass Used to create a tougher directional or full window tile.

Building Your Sentry And Maintaining it

Building Your Sentry [In-Depth]

  1. Open the UA 571-C Sentry crate
  2. Take out the plasteel Plasteel.png inside of the crate.
  3. Click the plasteel Plasteel.pngin your active hand to bring up the construction list, then select "turret frame".
  4. Find a wrench Wrench.png then click on the sentry to wrench it into place so it can't be moved.
  5. Use cable coil CableCoils.png on the turret frame
  6. Add the sentry turret on to the turret frame by clicking on it. ( You can find the sentry turret in the sentry crate.
  7. Add the sensor to the sentry by clicking on it.
  8. Click on the sentry with metal in your hand.
  9. Click on the sentry with a welder. Welder.gif
  10. Add in the powercell by clicking on the sentry with the power cell in hand. (You'll want a high capacity cell or a super capacity cell generally so that your sentry will rarely run out of power.)
  11. Click the sentry with an empty hand to turn it on.

Building Your Sentry [Quick]

  1. Sentry Crate
  2. Build turret frame from plasteel. Plasteel.png
  3. Wrench Wrench.png
  4. Cable coil. CableCoils.png
  5. Sentry turret added to turret frame.
  6. Sentry Sensor
  7. Metal Metal.png
  8. Weld. Welder.gif
  9. Powercell
  10. Turn on

Moving Your Sentry

  1. Turn off the sentry in the pop up window that appears when you click the sentry with an empty hand.
  2. Screw Screwdriver.png the sentry. (Will display the message that you unsecure the bolts.)
  3. Pull the Sentry to new location.
  4. Screw Screwdriver.png the sentry in the new position. (Will display the message that you secure the bolts)
  5. Click on the sentry with an empty hand to turn it on again.

Rotating Your Sentry

  1. Use a Wrench on the sentry when it's turned off.

Maintenance Of Your Sentry

  • Use a Welder on your damaged sentry to fix it.
  • To replace ammo or a powercell in a sentry just click on the sentry with the new ammo/powercell in your active hand.

Functions Of The Sentry

  • Clicking on the sentry whilst it is turned ON with a free hand will bring up a menu, this menu shows you current ammunition, power levels, % health remaining and gives you the option of swapping it's firing modes and directional lock.
  • Firing Modes - The sentry has two modes, Single Fire: A slow firing but more accurate mode, uses up ammunition at a slower rate, but is usually outperformed by the other firing mode; Burst Fire: A three round burst with moderate accuracy, this firing mode is for when you want to put the hurt on something, and the increased ammunition consumption rate is rarely an issue outside of lengthy confrontations, and even then the spare ammo case all sentries come with are enough to make it last quite a while.
  • Directional Lock - The sentry gun is equipped with a directional lock, leaving this on gives it a 180 degree field-of-fire in the direction it is facing, this mode has a long range, but as previously mentioned, only covers one direction. If you turn off the directional lock it'll set the turret into 360 mode, which will allow it to shoot at hostiles coming in from any angle, not just the one it's pointed at, HOWEVER, doing so DRASTICALLY reduces the range of the turret due to the extra stress this puts on the hydraulics and AI of the sentry gun.

APC Maintenance

So, someone decided to throw a grenade next to the APC or you just arrived to a broken APC and your SL has tasked you with fixing it whilst the squad holds off the incoming xeno tide. No need to panic as this section will get you to quickly repair that APC.

  1. First you'll want to whack off the cover; to do this just hit the APC with any sort of weapon, generally a combat knife is good for this.
  2. Take out the battery (Power cell) in the APC once the cover is off with an empty hand.
  3. Use a screwdriver on the APC.
  4. Use wirecutters on the APC.
  5. Use a crowbar no the APC.
  6. Build and APC frame from 2 metal sheets then click on the APC with the APC frame in hand.
  7. Use wires (Cable Coil) on the APC.
  8. Click on the APC with a power control module in hand.
  9. Use a screwdriver on the APC.
  10. Place a new battery (Power cell) in the APC. (Just click on the APC with the battery in hand.)
  11. Use a crowbar on the APC.
  12. Open up the APC pop up window once you've completed all previous steps and turn on the breaker.


Alright, so you wanna be the Hackerman huh? Well here's where you're gonna find out everything you need to know about breaking into places you shouldn't be entering.

You're going to want to start off the hack by ensuring you're wearing Budget/Insulated Gloves, and then with a screwdriver in your hand, clicking on the door you plan on hacking, this exposes the wires of the door and from here you'll branch off into one of the two following options:

Hacking the door open using a Multitool.

  • Alright, so after you've started the hack with the screwdriver, pull out your multitool and click on the door in question, this should bring up a menu that consist of a bunch of colored wires with the words PULSE and CUT next to them, further down you'll see some text telling you a bunch of systems are ON, look for the system titled 'Test Light', this governs the power flow of the door, finding the 'Test Light' wire and pulsing it will short out the system, allowing you some time to use a crowbar on the door and open it. In order to find the 'Test Light' wire though you'll need to go through the list of wires one by one, pulsing each of them and paying attention to which system they turn on or off, pulsing the 'Door Bolts' wire will lock the door immediately, pulsing it again will lift the lock, as long as the door has power at least, try to avoid this wire. Once you discover the 'Test Light' wire by pulsing it and seeing the text for the system change to 'Test Light is OFF', write down the color of the wire for future use, keeping in mind wires change every round, after this, close the menu, pull out a crowbar and with it in hand, click on the de-powered door, this will force it open for a couple of seconds before it closes and power returns to the system.

Hacking the door open without a Multitool, AKA, using Wirecutters.

  • Misplaced your Multitool? Or perhaps you forgot to get one in the first place, well don't worry you can still do the job as long as you've got everything else in your toolbelt, this guide follows the same steps as the Multitool guide up to the point where you'll need to start pulsing wires to find the test light, since you can't make use of that PULSE button you'll be testing out the CUT button instead, with Wirecutters in hand you'll want to start going through and cutting wires one by one, and preferably mending them if they aren't the 'Test Light' wire, so you don't cause any irreparable damage to the poor door. Be careful when cutting the 'Door Bolts' wire as it will drop them, and you will be unable to lift them without access to a multitool. After you've cut the 'Test Light' wire, use the Crowbar to open the door and you're golden.
  • You can also hack vendors by using a screwdriver on them to allow you to access the wires then, you can use a multitool to pulse the wires until you release the extra gear (The extra gear will pop up.), once that's done you'll know the exact wire to pulse each time to release the extra gear in the vendor.

Mine Placement

  • Work in Progress mine section needs to be started instead of sample text of what to put in.

How to effectively get the nickname 'disco inferno' like you're a god damn Dj throwing records out like Frisbee's.

  • General sample text on how Mine placement woks in CM.
  • Picture example if possible of how to place a mine
  • Where and when to mine. e.g securing the Fob, securing the assault flanks etc.

FOB Pointers

What makes a good FOB? Well, if it was a bad FOB it'd probably consist of nothing but a few tables and perhaps a metal barricade placed in the wrong direction.

  • Key things to remember when building an FOB are 'Can marines get around the FOB with ease?' 'Can marines shoot past these barricades?' and 'Am I fortifying one area too much and not focusing enough on the others?' by asking yourself this periodically, you'll take a step back and look at your work, and possibly notice a few mistakes here and there that can easily be fixed.
  • Any kind of barricade you build will only block projectiles coming from the direction it is facing, so try not to accidentally place all your metal barricades facing towards the inside of your FOB, lest some poor SADAR marine attempt to fire a rocket over it.
  • A good offense can be a great defense; should you notice an area of your FOB beginning to crumble at an alarming rate, instead of focusing materials on repairing this area, prepare a few barricades facing towards the breaking line and place some marines or sentry guns at them to over-watch the situation. Sure there might not be anything stopping Xenomorphs from running straight into your FOB, but they might think twice if the first thing they see as they walk past the remains of the walls they just melted through is the barrel of an M30 Autocannon backed up by a handful of Pulse Rifles.
  • Here is an example of a standard FOB that follows the above mentioned guidelines.

General Tips

  • Examining an incomplete Sentry frame will list what it is and isn't missing. This can help if you stumble upon somebody's half-assed arts n' crafts project, or if you find yourself forgetting steps mid-construction.
  • All vendors contain a 'contraband' wire, pulsing this wire after beginning the hack with a screwdriver will cause a few new items to show up in the vendor, but as a general warning, it is against Marine Law to hack the vendors on the Almayer, so keep an eye out for MP's before you accidentally cause trouble.
  • Plasteel and Metal are valuable resources sure, but just remember that you aren't the only person that needs them, don't hoard loads of building supplies otherwise you might find other players unable to perform their jobs.
  • In a pinch, even the average door can make a solid defense, by welding a door shut it will no longer be able to be wrenched open, either by Xenomorphs or a man wielding a crowbar. Hacking the door and forcing its bolts down has this same effect, but welding is substantially quicker and a lot safer when you've got bad guys breathing down your neck.
  • As an Engineer, it's in your job description to keep any defensive structures you or another engineer builds in tip-top shape, this may include having to repair metal barricades and the like in the midst of combat or replace melted structures with new ones, which is dangerous, but it's what you signed on for. This also goes for APC's and any broken lights you may see, you'll want to replace these post-haste so that marines may benefit from their existence.
  • Just as a general reminder, if you intend to be hacking open doors or pulsing wires in vendors, you'll want to be wearing Insulated Gloves, Budget Insulated Gloves work too, but aren't as good. Failure to wear the correct PPE* for your work environment will result in a hearty shock if you touch the wrong wire. (*Personal Protection Equipment)
  • You might've noticed that the welder is one of the two most important tools for an engineer to have, you may also have noticed it carries a measly 20u's of welding fuel before it needs to be refueled, or you could replace it with another welder that would eventually also need to be refueled. To do this, you'll need to find either a Welding Kit (It looks like two propane tanks were turned into a backpack, or some kind of futuristic jet pack) or a Fuel Tank (This one is a large gas canister that fills an entire tile, hard to miss it), the Welding Kit can be placed in the backpack slot for easy access, but carries less fuel than the Tank, the Tank carries a large amount of fuel, but can only be dragged around. After you've located your refueling utensil, have your welder in hand, make sure it is turned OFF (This part is key to success) and click on the Kit/Tank, you'll get a bit of flavor text saying 'the welder has been refueled' if you've done it correctly.