Iron Nest Endings: How to Unlock All Four

Community testing has identified four endings in IRON NEST: Heavy Turret Simulator, and all of them are decided by what you do in the final mission. For most routes that means no full campaign replay — the branch comes down to which shell you fire into the city, or whether you turn the gun on your own side.

This page explains first, without spoilers, how the ending is decided, then lists the exact reported trigger for each ending in a clearly marked spoiler section. The details come from early post-release player testing, so read them as community findings rather than official documentation.

How Many Endings Does Iron Nest Have?

Player testing on the game’s subreddit identifies four distinct endings, and a community video titled “IRON NEST: Heavy Turret Simulator - ALL ENDINGS” shows each of them. Players refer to them as Ending 1 through Ending 4; the numbering is a community convention rather than an in-game label.

Just as important is where the decision happens. The same testing reports that the ending is determined primarily by actions in the final mission, so the branching is concentrated at the end of the campaign instead of being accumulated across every earlier operation.

What Decides the Ending (Spoiler-Free)

Two choices matter in the finale: what you fire into the city, and who you fire at. The shell you load for the last shot steers you toward three of the four endings, while the remaining one comes from deliberately attacking your own side instead of the assigned target.

Because the trigger sits inside a single mission, players report that most endings can be reached without replaying earlier operations. The exception is the treason route, which rewards preparation started well before the finale — saved funds, stockpiled ammunition and reconnaissance past the initially revealed map. Decide which outcome you want before the final operation begins, and prepare accordingly.

All Four Ending Triggers (Major Spoilers)

Stop reading here if you want to find the triggers yourself. Everything below lists the exact conditions players have reported, in the community’s numbering.

• Ending 1 — fire a gas shell into the city. The shell must be one the game classifies as offensive gas. Players list Cyanogen, TEAR and Phosgene, and report that Flechette is also counted as gas for this check.
• Ending 2 — fire a propaganda shell into the city. A PRPG or Propaganda shell triggers this ending, and one player reports that STAR can trigger it as well.
• Ending 3 — the treason route. Destroy the King, the General and every blue allied artillery unit. Some allied guns sit outside the initial aerial reconnaissance coverage, so they have to be located before they can be destroyed.
• Ending 4 — fire a nuclear or other non-gas offensive shell into the city. Community reports say ordinary HE can trigger it, so a nuclear shell is not the only route.

If you are unsure which of your rounds fall into each category, the shell types guide breaks down the ammunition roster.

Preparing for the Treason Route (Ending 3)

Ending 3 is consistently described as the most preparation-intensive route. Players report needing enough Requisition Credits and preloaded ammunition to fight through every allied battery, plus scouting beyond the area revealed when the mission begins, because some of the guns you must destroy are not on the initially revealed map.

Although the ending choice is concentrated in the finale, the same community discussion notes that this expensive route can still benefit from saving resources during earlier missions. If Ending 3 is the goal, treat the whole campaign as buildup — the missions guide covers the operations leading up to it.

Before You Start the Final Mission

Players who tested the endings recommend two precautions before the final operation. First, preserve a backup save whenever the game’s save system allows it, so a wrong shell or one missed allied gun does not cost a full replay of the mission.

Second, keep your own record as you go. Note which units you have destroyed and how each loaded shell is classified, because an ambiguous trigger can otherwise force you to repeat the finale just to learn which branch you actually hit.

How Reliable Are These Triggers?

Every condition above comes from early post-release community testing, not from an official statement. Where reports are uncertain — the Flechette and STAR classifications are the named examples — players are advised to retest those shells against the current patch.

The four-ending structure itself is consistent across both community threads and the all-endings video, so the broad picture is stable even where individual shell classifications remain open to retesting.

Bottom Line

Four endings, one deciding mission. Pick your final shell — gas, propaganda, nuclear or another non-gas offensive round — or turn the turret on the King, the General and every blue battery, and keep a backup save so each route only has to be done once.