Ironman mode is an optional gameplay flag that restricts control over the saved game, disallowing the player from correcting mistakes and changing decisions made during the course of play. Ironman can be enabled from the settings screen when starting a new campaign. Playing in Ironman is required to unlock Steam achievements; however, it is also possible to play in Ironman and not be eligible to unlock achievements, such as by playing with a mod that changes the checksum enabled (broadly, any mod that changes gameplay in some way).
When beginning a new game, the player is given the option to play in Normal or Ironman mode from a pop-up box. If Ironman is selected, the box will also say whether it is possible to unlock achievements.
To gain Achievements one needs to be in Ironman and obey a number of restrictions:
- Only a single save will be stored; it is thus impossible to load an earlier save if something goes wrong (unfortunately, this includes save game corruption).
- The game saves automatically every 3 months, on quitting, and whenever almost any decision is taken (such as declaring war).
- Save files can be stored in the Steam Cloud or on a local drive, but are encrypted and cannot be edited.
- Historically lucky nations cannot be disabled.
- Bonuses to human players cannot be enabled (AI bonuses can still be enabled).
- Easy difficulty is unavailable.
- The console is disabled.
- The player is not allowed to load any saved game while in-game. Loading a save requires exiting to the main menu.
As Ironman is set to autosave at monthly intervals, on high speeds the game may frequently freeze for a few seconds as it saves. This can be mitigated by playing on a high-speed storage device such as a solid-state drive. Local saves are faster than Steam Cloud saves as they don't have to be compressed when saving, but you will also need to place your "My Documents" folder on your high-speed storage device. Additionally caused by Ironman mode's regular saving is occasional loss of connection to Steam when on a slow or unreliable Internet connection, which requires waiting for Steam to reconnect in order to resume gameplay.
Any bugs (such as the well documented "endless war" bugs) can ruin an Ironman game as well.
Save file location
There are two options for save locations for Ironman. Local Ironman saves are always uncompressed and are stored in:
Documents\Paradox Interactive\Europa Universalis 4\
- (for Linux)
~/.local/share/Paradox Interactive/Europa Universalis IV/save games/
If choosing to save on Steam Cloud, the save will be always compressed and uploaded to the Steam servers. A backup is also kept locally on your computer, at:
C:\Program Files (x86)\Steam\userdata\<YOUR STEAM ID>\236850\remote\save games
For Mac user is at:
~/Library/Application Support/Steam/userdata/<YOUR STEAM ID>/236850/remote/save games
Steam Cloud synchronization must be enabled for the game in the Steam library (right click on Europa Universalis IV, click Properties, click on the Updates tab) and in the Steam settings (Steam>Settings, click on the Cloud tab).