diff --git a/src/main.c b/src/main.c
index 7064f61..d72c701 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1,6 +1,6 @@
 /*
   Project name ......: Plague
-  Version ...........: 1.3.7
+  Version ...........: 1.3.8
   Last modification .: 8 June 2021
 
   code and assets provided with licence :
diff --git a/src/mutation_engine.h b/src/mutation_engine.h
index 8b2ec28..8a5d8da 100644
--- a/src/mutation_engine.h
+++ b/src/mutation_engine.h
@@ -5,7 +5,7 @@
 #include "display_engine.h"
 
 // Basic limit research
-#define RESEARCH_LIMIT 300
+#define RESEARCH_LIMIT 250
 
 // mutation_table : contain the map of the mutation available
 struct mutation_table