diff --git a/sc2/doc/users/manual.txt b/sc2/doc/users/manual.txt
index 453bb7adb..a53511a18 100644
--- a/sc2/doc/users/manual.txt
+++ b/sc2/doc/users/manual.txt
@@ -174,6 +174,17 @@ The default.
 Use the PC intro and ending sequences and slide shows. These will be also
 played if you do not have 3DO movies, regardless of -i option.
 
+	--shield pc
+
+Use PC style static slave shield graphic.
+Default.
+
+	--shield 3do
+
+Use 3DO style throbbing slave shield graphic. This somewhat increases the
+load on CPU while in orbit. Do not use if your CPU cannot handle that.
+
+
 NOT OFFICIALLY SUPPORTED OPTIONS
 
 The following options may not exist in all builds and can change without