diff --git a/src/AvatarFetcher.java b/src/AvatarFetcher.java
index 48fd60d..37e5244 100644
--- a/src/AvatarFetcher.java
+++ b/src/AvatarFetcher.java
@@ -16,8 +16,7 @@ public AvatarFetcher(CodeSwarmConfig cfg) {
   }
   
   public String fetchUserImage(String username) {
-    //Override fetchUserImage in your Avatar Fetcher
-    return null;
+    throw new RuntimeException("Override fetchUserImage in your Avatar Fetcher");
   }
   
   protected static String getFilename(String key){
diff --git a/src/NoAvatar.java b/src/NoAvatar.java
new file mode 100644
index 0000000..3b64af8
--- /dev/null
+++ b/src/NoAvatar.java
@@ -0,0 +1,11 @@
+
+public class NoAvatar extends AvatarFetcher {
+
+  public NoAvatar(CodeSwarmConfig cfg) {
+    super(cfg);
+  }
+
+  public String fetchUserImage(String username) {
+    return null;
+  }
+}
diff --git a/src/code_swarm.java b/src/code_swarm.java
index 58369ac..2624f4b 100644
--- a/src/code_swarm.java
+++ b/src/code_swarm.java
@@ -243,7 +243,7 @@ public void setup() {
 
     isInputSorted = cfg.getBooleanProperty(CodeSwarmConfig.IS_INPUT_SORTED_KEY, false);
     
-    avatarFetcher = getAvatarFetcher(cfg.getStringProperty("AvatarFetcher","AvatarFetcher"));
+    avatarFetcher = getAvatarFetcher(cfg.getStringProperty("AvatarFetcher","NoAvatar"));
 
     /**
      * This section loads config files and calls the setup method for all physics engines.