Iron Marines+ Lights Out: How to Beat the Secret Mission

To beat the secret Lights Out mission in Iron Marines+, advance through the darkened facility one sector at a time, use long-range fire to clear automated emplacements before they engage, and hold tight defensive formations around each power relay until the grid activates.

Recommended Squad Composition and Roles

The mission's narrow corridors and low visibility make fragile, mobile builds risky. Anchor your squad with a resilient frontline hero and back them with dedicated anti-armor and swarm-clearing units.

Taggins provides temporary invulnerability shields that allow safe scouting into unlit rooms, while Kara offers heavy area-of-effect explosives to clear dense clusters before they reach your line. Pair your chosen hero with Snipers to exploit line-of-sight advantages, while Brawlers or mechanical heavy walkers physically seal choke points.

Step-by-Step Route Through the Facility

Unpowered sectors conceal enemy turrets and ambush triggers. Moving too quickly risks pulling multiple waves into the dark simultaneously.

1. Secure the drop zone: Hold position near the starting wall and eliminate the initial security bot patrol as it paths toward you.
2. Scout ahead with your commander: Move your hero forward just enough to reveal enemy emplacements, then pull back slightly to draw mobile escorts into your Snipers' firing range.
3. Trigger the first relay: Step onto the power console to start the activation sequence. Form an arc facing the adjoining vents and eliminate incoming ambush waves until overhead lighting is restored.
4. Follow illuminated conduit paths: Advance strictly along the floor cables leading to secondary hubs. Straying into unpowered side corridors triggers optional encounters with dormant combat units.
5. Clear and secure the central core: Use your hero's defensive skills or crowd-control abilities to absorb initial rocket fire in the main chamber, eliminate the high-tier defenders, and lock down the terminal.

Defending Active Power Consoles

Every console activation triggers defensive counterattacks converging on your position.

Keep your frontline units positioned between the terminal and the main entry hallway. Cluster your ranged units close to the console in the center rather than spreading them across multiple access points. This central positioning lets your Snipers pivot instantly between flanking chutes without losing attack uptime. Stagger your frontline slightly if incoming waves include heavy explosive units to avoid concentrated splash damage. Never pursue surviving enemies into unlit corridors during an active holdout; hold the lit zone and let them approach your firing line.

Enemy Threat Hierarchy

Direct manual targeting against the most dangerous units to prevent squad attrition:

• Automated Sentry Cannons: High-damage stationary guns. Pick them off from long range with Snipers before moving the main squad into their field of fire.
• Kamikaze Repair Drones: Fast-moving units that explode on contact. Eliminate them with hero abilities or Flamethrowers before they reach your front line.
• Shielded Enforcer Mechs: Armored units with directional shields. Draw their attention with your hero, then strike with kinetic fire once their shields face away from your squad.
• Security Grunts: Standard combat units with moderate damage. Let passive splash damage and standard fire clear them while manual orders target higher-priority threats.