diff --git a/changelog.txt b/changelog.txt
index 59053953..2be7de50 100644
--- a/changelog.txt
+++ b/changelog.txt
@@ -5467,4 +5467,13 @@ Mostly bugfixes:
 - fixed the distance display in the expansion mode
 - fixed file dialog closing incorrectly
 - fixed Orb of Sword blocking strong wind
-https://zenorogue.blogspot.com/2025/08/hyperrogue-131.html
\ No newline at end of file
+https://zenorogue.blogspot.com/2025/08/hyperrogue-131.html
+
+2025-08-17 21:03 Update 13.1a:
+- improved selection of player shape: four new shapes, save/load customized characters, the character is centered correctly
+- fixed slaying + discord graphics
+- other active orbs now extend the duration of Orb of Recall
+- fixed CR5 and MCR not appearing in PTM
+- alt unlock condition for CR6
+- fixed the floor graphics in dual tilings
+- finding the music file in some installations should be fixed
diff --git a/hyper.h b/hyper.h
index 351bf725..148dfa3f 100644
--- a/hyper.h
+++ b/hyper.h
@@ -13,8 +13,8 @@
 #define _HYPER_H_
 
 // version numbers
-#define VER "13.1"
-#define VERNUM_HEX 0xAA20
+#define VER "13.1a"
+#define VERNUM_HEX 0xAA21
 
 #include "sysconfig.h"