Iron Nest Mission 6: Siege of Cartagena - Solutions

Worked example: Bearing, range, charge and elevation figures below come from a sample playthrough. Enemy spawns and your Iron Nest’s position vary each run — always measure on the map and follow the in-game ballistic calculator.

Mission Critical Strategy: Fighting From Two Places at Once

Siege of Cartagena is the campaign’s first Emergency Move mission, and the move is not a complication bolted onto the firefight — it is the firefight.

You begin the mission in an excellent firing position with clear lines onto the outer coastal batteries. You will not stay there. Once the enemy locates your muzzle blast, a counter-barrage comes in, and the only way to survive it is to relocate Iron Nest several kilometres and rebuild every firing solution from a new origin.

The mission therefore has two distinct halves, and the trap is treating them as one continuous engagement:

Phase	Firing origin	Valid data
Before the move	Original position	Original bearings and ranges
After the move	New position (several km away)	Nothing from the first table

The most common failure is not dying to the barrage — it is surviving the move and then firing the old numbers. A bearing is only meaningful relative to a specific origin. Move the origin and every angle you calculated becomes wrong by the same margin.

The three jobs, in priority order

1. Clear the outer batteries. They are what forces the counter-barrage in the first place.
2. Move when told. Not one shell later.
3. Protect the infantry corridor. The friendlies are breaking out at 11.20 km and smoke is the only shell in your locker that helps them directly.

Job 3 is the one operators forget, because it does not look like combat. A smoke screen that lands two minutes late is indistinguishable from no smoke screen at all.

Why the smoke shot is not optional

The friendly breakout is happening whether or not you support it. If the corridor is not screened, the infantry take fire crossing open ground and the mission’s objective set fails — even if you personally destroyed every gun on the coast. The smoke shell is the mission-winning shot; the high explosive is the mission-enabling one.

Pre-Calculated Firing Solutions

Opening table — outer coastal batteries (original origin)

Target	Target Grid	Turret Bearing	Target Range	Powder Charges	Elevation (θ)	Ammunition
Outer Coastal Battery WEST	Grid B4 2.6	285.0°	13.60 km	3 Charges	54.40°	H (High Explosive)
Outer Coastal Battery EAST	Grid C6 8.1	298.4°	12.40 km	3 Charges	49.60°	HCHE

Post-move table — after Emergency Move (new origin)

Target	Target Grid	Turret Bearing	Target Range	Powder Charges	Elevation (θ)	Ammunition
Secondary Bastion NORTH	Grid C1 5.4	264.0°	14.80 km	3 Charges	59.20°	H (High Explosive)
Friendly Corridor — Smoke Screen	Grid A7 3.3	210.0°	11.20 km	3 Charges	44.80°	SMK (Smoke)

[!WARNING] The two tables are not interchangeable. Post-move bearings and ranges are computed from the new firing origin. Firing the opening table after the move lands every shell in the sea.

Step-by-Step Operator Routine

Phase 1: Requisition and Plot (Timer: Stopped)

1. Buy 2 H shells, 2 HCHE shells, and 3 SMK shells. The smoke allowance is deliberately generous — you may need to re-screen the corridor.
2. Buy 18 powder charge bags. The Emergency Move forces a full re-charge cycle and the last thing you want is to run dry mid-recovery.
3. Plot the two outer batteries (B4 2.6, C6 8.1) and confirm both bearing readings independently.

Phase 2: Clear the Outer Batteries (Opening Origin)

1. Load Left Gun: 1 H + 3 charge bags. Elevation 54.40°.
2. Load Right Gun: 1 HCHE + 3 charge bags. Elevation 49.60°.
3. Traverse to 285.0°, select LEFT GUN, fire. Confirm the west battery is silent.
4. Traverse +13.4° to 298.4°, select RIGHT GUN, fire. Confirm the east battery is silent.

Phase 3: Emergency Move (Immediate)

1. The moment the counter-barrage warning appears, execute the Emergency Move. Do not complete the current cycle.
2. At the new position, request a Position Report and re-plot your own coordinates first. You cannot compute a bearing before you know where you are standing.
3. Rebuild the firing card from the post-move table. Re-charge both guns — the move invalidates your charge state as much as your angles.

Phase 4: Screen the Friendly Corridor (Highest Priority)

1. Load SMK with 3 charge bags, elevation 44.80°, bearing 210.0°.
2. Fire the smoke shell before engaging the secondary bastion. The infantry are already moving.
3. Watch the corridor. If the screen starts to dissipate before the breakout completes, fire a second SMK shell at the identical solution — smoke screens are re-laid, not extended.

Phase 5: Reduce the Secondary Bastion

1. With the corridor covered, load H with 3 charge bags and re-lay to 59.20°, bearing 264.0°.
2. Fire and confirm. The northern bastion is the last hard target in the mission.
3. If the teleprinter reports the bastion still active, re-fire once with the same solution before adjusting anything — the first round may simply have landed in dead ground.

[!IMPORTANT] Operator Rule: In a mission with an Emergency Move, treat the move as the midpoint of the mission, not an interruption to it. Everything before it is a preparation for surviving it; everything after it is a new engagement with a new map.