--- a/HWPFormat.wiki	Tue Apr 25 22:14:15 2017 +0100
+++ b/HWPFormat.wiki	Wed Apr 26 03:15:35 2017 +0100
@@ -34,6 +34,12 @@
 
 It is a special case when you have multiple HWPs activated, when some of them try to include a file with identical name. This is a conflict, see the conflict section for more information about this.
 
+==== Custom ammo icons ====
+Normally, all files in an HWP can overwrite/replace existing files found in `Data`.
+
+But in 0.9.23, there is an unique exception: `Graphics/AmmoMenu/Ammos.png` and `Graphics/AmmoMenu/Ammos_bw.png` will be overlayed over the original images `Graphics/AmmoMenu/Ammos_base.png` and `Graphics/AmmoMenu/Ammos_bw_base.png`, respectively. This is useful if you only need to replace a few certain ammo icons, and not the entire set of ammo icons. This is especially important to ensure forwards-compability of your sidecar HWPs for your scripts (see below).
+
+For example, if you want to replace the “Air Attack” icon with a crosshair icon, but leave everything else alone, just draw the cross hair icon on the correct position and make all other frames fully transparent.
 
 == Possible locations for HWPs ==