--- a/Forts.wiki	Mon Sep 14 15:56:52 2015 +0000
+++ b/Forts.wiki	Tue Sep 15 17:46:48 2015 +0000
@@ -7,9 +7,9 @@
 == Creating a fort ==
 Creating a fort is a relatively simple task.
 
-To create a fort, you have to create two graphics in PNG format, for the fort on the left side and for the fort on the right side. Normally these images are just mirrored, but you may want to apply some graphical tweaks for written text or shadows.
+To create a fort, you have to create one or two graphics in PNG format, one for the fort on the left side and optionally (since 0.9.22) one for the fort on the right side. Normally these images are just mirrored, but you may want to apply some graphical tweaks for written text or shadows.
 
-All transparent pixels are open air and all opaque pixels are part of the fort.
+All transparent pixels are open air and all opaque and semitransparent pixels are part of the fort.
 
 Both images have to be at a size of exactly 1024×1024 pixels.
 
@@ -23,6 +23,8 @@
 }}}
 for the right fort. “fortname” will be the name how the fort will appear in Hedgewars, replace it with the name you want.
 
+Since version 0.9.22, `fortnameR.png` can be omitted if it is just a perfect mirror image of `fortnameL.png`.
+
 Please try to only use alphanumeric characters and the underscore when choosing a name.
 
 When you are finished, save the files in `Data/Forts` of your Hedgewars data directory.