Iron Marines+ Mission 18 Guide: How to Beat 33 Seconds With Mark X

To beat Mission 18: 33 Seconds in Iron Marines+ with Mark X, deploy the hero as a frontline damage sponge at the primary chokepoints, protect your fragile ranged squads behind his armor, and cycle missile strikes to wipe dense enemy clusters before countdown timers expire.

Positioning Mark X on the Frontline

Mark X's armor and defensive shielding make him the primary frontline anchor for Mission 18's narrow corridors. Station Mark X at the front of your defense line so advancing melee enemies and ranged attackers acquire him as their target instead of your support squads.

• Damage absorption: Activate Mark X's defensive shield when heavy burst fire arrives.
• Wave clearing: Fire Mark X's missile barrage into tightly clustered groups to strip shields and soften armor before enemies reach your line.
• Safety boundary: Keep Mark X within firing range of your support units and turrets. Do not scout ahead into the fog of war alone, as concentrated enemy focus fire will overwhelm his health before support can react.
• Repositioning: When Mark X drops below 30% health, step him back behind allied barriers or Guardian shield auras. Let stationary defenses draw aggro while his health recovers, then move him back to the front once abilities refresh.

Recommended Squad Composition

Mark X requires balanced squad support to handle split attack lanes and eliminate threats efficiently.

Station Snipers behind Mark X on elevated ground or behind barricades to maximize their line of sight. Keeping repair support alive preserves your ether for turret construction and upgrades rather than squad replacements.

Chokepoint and Turret Setup

Mission 18 funnels enemy waves through sharp corners and tight bottlenecks before they reach your primary objectives. Setting up interlocking defenses at these points forces hostiles into compact groups, maximizing the impact of Mark X's missile barrage.

1. Secure the bottleneck: Establish your defensive perimeter where enemy paths converge.
2. Build supporting turrets: Construct cannon or laser turrets at nearby build nodes to provide continuous baseline damage. Use turrets to draw secondary aggro while Mark X blocks the main path.
3. Layer the backline: Place Guardians and Snipers directly behind Mark X so ranged attackers cannot flank them.
4. Hold or fall back: If a lane is overwhelmed, pull your squad back to the next narrow passage as a unit. Avoid retreating into open terrain where your squads can be surrounded.

Target Prioritization During Wave Timers

Survival during timed countdown sequences requires manual focus fire so high-threat targets do not breach your perimeter:

• Elite Disruptors and Casters: Target these units immediately with Mark X's abilities to stop debuffs and channeled abilities.
• Ranged Artillery Walkers: Manually command Snipers to eliminate distant siege walkers before their explosive attacks splash across grouped units.
• Heavy Melee Bruisers: Body-block these units directly with Mark X while support squads apply continuous armor-piercing damage.
• Light Swarms: Let passive turret fire and close-range infantry clear swarms. Save Mark X's missile cooldowns for dense groups or elite targets.

Pre-Mission Upgrades

Before starting Mission 18, allocate research points into hero cooldown reduction, base armor increases, and hero weapon damage. Shortening Mark X's ability cooldowns ensures defensive shields and missile strikes are ready for each timed wave.