Iron Blight Difficulty, Ironman and Cassette Tape Mode

Three settings, three achievements

Iron Blight separates difficulty from modes, and layers a modifier system over both. The achievement list is the clearest public record of what exists:

Those are three separate campaign completions unless the game lets you stack them, which is not something Ronesans Interactive has documented. Plan for three runs and be pleasantly surprised.

The modifier system, and the Sickness change

Modifiers sit on top of difficulty. The clearest evidence of how they work comes from Patch 1.01, which states that the Sickness modifier is now inactive by default on Hardcore difficulty. Two things follow from that sentence:

• Sickness is a modifier, not a difficulty feature, and it can be toggled.
• Before 26 August 2026, a Hardcore run was also automatically a Sickness run. If you bounced off Hardcore during launch week, you were fighting a harder configuration than the one shipping now.

The same patch note also states that the campaign-completion achievements — End Of The Line, Recorded, Blightbreaker and Iron Might, plus the hidden Red Express — now unlock “based on active modifiers”. Whatever modifiers you run with, the game is watching them at the moment you finish.

Players have asked about the infection mechanic in the forums under the title “Unclear about infection”, which suggests the game does not fully explain Sickness in-game either. We are not going to fill that gap with a guess; when the developers describe it, this page gets updated.

What Cassette Tape Mode is

Named as a mode rather than a difficulty, with its own achievement, and confirmed to interact with the modifier system through the Patch 1.01 achievement note. Beyond that, Ronesans Interactive has not published a description of what it changes, and we will not invent one from the name.

More modes are planned

Asked in the forums whether content was coming past the two chapters, a developer replied that the team is planning a completely new game mode and new modifiers, adding that other things are planned but could not be guaranteed. That is the firmest statement available; the roadmap page separates it from the looser mentions.

Before you commit to a long run

Check the patch history first. Several launch-week issues affected exactly the kind of run you cannot redo cheaply — achievements that did not fire on completion, save triggers that were repositioned, and items that did not carry between chapters. An Ironman clear is a bad time to discover any of those.