diff --git a/engines/hdb/ai.h b/engines/hdb/ai.h
index 2b9668ab045..c1cee843a82 100644
--- a/engines/hdb/ai.h
+++ b/engines/hdb/ai.h
@@ -372,6 +372,8 @@ struct AIEntTypeInfo {
 	void (*initFunc2)(AIEntity *e);
 };
 
+extern AIEntTypeInfo aiEntList[];
+
 struct CineCommand {
 	CineType cmdType;
 	double x, y;