diff --git a/src/formats.c b/src/formats.c
index 6e9f6545..d721cf43 100644
--- a/src/formats.c
+++ b/src/formats.c
@@ -460,6 +460,7 @@ static const char* extension_list[] = {
     "spsd",
     "spw",
     "ss2",
+    "ssd", //txth/reserved [Zack & Wiki (Wii)]
     "ssm",
     "sss",
     "ster",