diff --git a/src/mame/drivers/namcos2.c b/src/mame/drivers/namcos2.c
index 830dfe521cb..3569591297e 100644
--- a/src/mame/drivers/namcos2.c
+++ b/src/mame/drivers/namcos2.c
@@ -34,8 +34,11 @@ known issues:
     Suzuka 8 Hours II
     - some sprite cropping issues
 
-    Legend of Valkyrie
+    Valkyrie No Densetsu
     - gives ADSMISS error on startup
+       Writes 0x0010 -> [0x10fbfc], 0x0000 -> [0x10fbfe], 0x0000 -> [0x10fc00], 0x1234 -> [0x10fc02] at PC=0x3d208, then does some writes to video related
+       devices then it tries to check if [0x10fbfc] is equal to 0x1234 (at PC=0x3d8f8), fails in any case if not.
+       Worth mentioning is that 0x3d202 contains a check with work RAM address 0x10fe5c. If zero the program flow writes 0x1234 on [0x10fbfc] instead.
 
     Bubble Trouble (Golly Ghost II)
     - no artwork