Binding of Isaac Afterbirth+ Receives New Patch Notes soon after its Birth

Binding of Isaac Afterbirth+ Receives New Patch Notes soon after its Birth

Binding of Isaac Rebirth was treated with a (near) New Year’s baby with the Afterbirth+ expansion. Less than half a week later, the sizable update has received its first patch fixing up some bugs. A lot of these changes had to do with squashing the usual programming bugs that show up with most releases.

However, a large amount of attention was focused on cleaning up one of the large features of the expansion: namely the mod support. The ability to tweak or overhaul Isaac has been one that ardent fans of the series (myself included) have been wanting ever since the original BoI came out in late 2014. After this patch, modding now supports joystick inputs, adjusting player stats, and the ability to record changes easier with HTML documentation.

The one part of the patch notes that was unfortunately vague was the actual changes to the main game: ‘Various adjustments for balance and fairness’ is written with one of the BoI hearts put next to it. The game’s creator, Edmund McMillen, shed a bit of light on these changes through his twitter page but unfortunately didn’t go into that much detail.


He also mentioned that this won’t be the last of the timely updates:


BoI is a very complex game and its not surprising that anything new added to the hundreds of stacking items, and dozens of interplaying rooms and monsters wouldn’t cause some issues. I remember similar things happening when the Wrath of the Lamb expansion came out for the original game. However, Afterbirth+ still follows McMillen’s penchant for releasing densely packed (and thought out) content for his popular roguelike.

With continued patch support and tweets encouraging players to report bugs, it’s certain that Isaac’s latest trip down into hell will get smoother as time progresses. Currently this expansion is only available for the PC with PS4 and Xbox One support expected in Spring 2017. The full patch notes can be found below.


  • Fixed a Windows crash caused by an exe modification step in the build process
  • Fixed a crash related to loading a game save after smelting trinkets
  • Fixed a crash on startup related to save data
  • Fixed a crash involving an item that would try to spawn doors in Greed/Greedier mode
  • Fixed a bug where the player could be hurt by certain fires spawned by their own items
  • Fixed a bug where the boss clear music could play too soon
  • Adjusted steam cloud save detection
  • Various adjustments for balance and fairness

Mod tools:

  • Fixed a display issue and some default path issues with room editor
  • Fixed a Mac issue with missing libraries that made the Mac ModUploader
  • impossible to launch without a specific dev environment installed

Modding API:

  • Generated comments for HTML documentation
  • Added descriptions of mod callback conditions, arguments and return values, in enums.lua and in HTML documentation
  • Changed signature of MC_EVALUATE_CACHE callback to pass the player entity
  • Removed some duplicated casts: Isaac.ToPickup and Isaac.ToEffect. Instead use entity:ToPickup and entity:ToEffect
  • Added some missing entity casts: ToBomb, ToLaser, ToKnife
  • Added some methods to player to get joystick inputs
  • Made player stats modifiable by mods
  • Removed getters for readonly player stats, since they were made redundant
  • Added functions such as Isaac.WorldToScreenPosition to convert game coordinates to rendering coordinates