Here is the full list of all 76 Iron Marines achievements. It takes around 25-30 hours to unlock all of the achievements on Windows.
Complete all Campaign Missions in Impossible difficulty.
Defeat Nexus, the Raad Vanguard Master, in Impossible difficulty.
Win Spec Op 'The Last of Them' in less than 7 minutes.
Kill 50 Alpha Fenrirs during a single try of stage 18.
Help the frozen, weird-looking alien squirrel get his preferred food on stage 18.
Help the squad of funny penguins achieve maximum coolness on stage 15.
Recruit a total of 41 fighters in the Ga’r Warhalls.
Find the 6 Immensity Stones to awake the awesome Mitten of Tranos.
Defeat Mr: Rob070 in Impossible difficulty.
Defeat 50 tentacles in Mission 13.
Search for the ultimate answer buying 42 different upgrades.
Complete Spec Op Laser Tag with the prototype Dropgun unharmed.
Help the Doctor travel through the timey wimey stuff in Mission 11.
Make the Compactors kill 50 Peripheroids.
Defeat the Fell Tyrant in Impossible difficulty.
Have at least 4 Brawlers active at the same time in Mission 8.
Destroy the Fell Bishop's cocoon in less than 4 minutes.
Defeat Nexus, the Raad Vanguard Master, in Normal or Veteran difficulty.
Destroy a total of 72 Ice Blocks.
Complete Mission 7 without losing any Squads.
Teleport all colonists to safety in Spec Op Darkest Hour.
Defeat the Fell Bishop in the Spec Op A New Despair in less than 30 seconds.
Destroy 30 Raad Portals before any enemy can enter our galaxy through any of them.
Find the 4 mischievous kids lost in the snow on stage 19.
Destroy a total of 46 Raad Carriers.
Kill a Spammer before it spawns any Inductors.
Beat the Spec Op 'The Colour out of Space' having destroyed all Bishop cocoons in the process.
Complete a Mission with at least one Brawler, one Shellstorm and one Firewalker at the same time.
Have 3 Heroes reach maximum level.
Have 4 Ranger Squads fighting at the same time in a single Mission.
Defeat Mr: Rob070 in Normal or Veteran difficulty.
Deploy any Hero to battle 100 times.
Help Sandro unlocks his cowabungous inner self.
Build a total of 149 Towers.
Teleport the five missing Captains scattered in Sagan-1.
Deploy 77 Empyrean squads onto the battlefield.
Free the cute alien from The Claw's grasp in MIssion 12.
Kill a total of 150 Jackbots resurrected by Oculus.
Spend 10000 Credits at the Arsenal.
Save all base colonists in MIssion 5.
Kill 20 or more enemies in less than 3 secs.
Capture all 3 Core Processor's switches without ever losing any of them in Mission 11.
Complete the Spec Op In Brightest Day with both Power Cores active.
Kill 343 Peripheroids.
Have 100 of your Squads die. They will be missed.
Help the broken Protocol Droid on Mission 10.
Have the worm throw 5 Holy Hand grenades at the enemies' faces.
Earn a total of 5000 Credits.
Have a Hero reach max level.
Beat Spec Op Into Darkness with all survivors.
Kill 7000 enemies.
Earn more than 5000 Techpoints.
Complete Mission 9 without losing a single Squad, like a miniature giant space hamster could do.
Destroy the same Assembly Center 3 times.
Defeat the Fell Tyrant in Normal or Veteran difficulty.
Complete Mission 4 only deploying Mechas.
Extract 10000 Etherwatts.
Kill 4000 enemies.
Attack 1000 times with Rocket Towers.
Wake 21 Grimcrushers from their stone slumber.
Rain down a total of 100 Dropguns to the battlefield.
Save the Ambassadress, save the world!
Kill 17 Etherleeches before they drain your Etherwatts storage.
Kill a total of 300 enemies in Emergency Frequency Spec Op.
Destroy 11 Fell Refineries.
Spend more than 1987 Etherwatts in a single Mission.
Help the space monkeys get the secrets of the Monolith in Mission 4.
Destroy 8 Worm Cannons in a single Mission.
Target to shoot 9 alien jellyfish until they explode.
Rescue all 4 wounded soldiers in Mission 3.
Kill 500 enemies.
Extract 1000 Etherwatts.
Buy any Upgrade from our wonderful selection.
Complete Mission 2 with the COMSAT taking no damage at all.
Complete Mission 1. We knew you could do it.
Click their portrait repeatedly to annoy a Hero during a Mission. They like it!