diff --git a/forge-ai/src/main/java/forge/ai/ComputerUtil.java b/forge-ai/src/main/java/forge/ai/ComputerUtil.java
index a0b5f377480..046c3dd0cf1 100644
--- a/forge-ai/src/main/java/forge/ai/ComputerUtil.java
+++ b/forge-ai/src/main/java/forge/ai/ComputerUtil.java
@@ -19,6 +19,7 @@ package forge.ai;
 
 import com.google.common.base.Predicate;
 import com.google.common.collect.ArrayListMultimap;
+import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Iterables;
 
 import forge.ai.ability.ProtectAi;
@@ -1704,6 +1705,10 @@ public class ComputerUtil {
     }
 
     public static String chooseSomeType(Player ai, String kindOfType, String logic, List<String> invalidTypes) {
+        if (invalidTypes == null) {
+            invalidTypes = ImmutableList.<String>of();
+        }
+
         final Game game = ai.getGame();
         String chosen = "";
         if( kindOfType.equals("Card")) {
diff --git a/forge-gui/src/main/java/forge/player/PlayerControllerHuman.java b/forge-gui/src/main/java/forge/player/PlayerControllerHuman.java
index 134da91244f..42ef21f1392 100644
--- a/forge-gui/src/main/java/forge/player/PlayerControllerHuman.java
+++ b/forge-gui/src/main/java/forge/player/PlayerControllerHuman.java
@@ -588,9 +588,11 @@ public class PlayerControllerHuman extends PlayerController {
      * @see forge.game.player.PlayerController#chooseSomeType(java.lang.String, java.lang.String, java.util.List, java.util.List, java.lang.String)
      */
     @Override
-    public String chooseSomeType(String kindOfType, SpellAbility sa, List<String> validTypes, List<String> invalidTypes, boolean isOptional) {
+    public String chooseSomeType(final String kindOfType, final SpellAbility sa, final List<String> validTypes,  List<String> invalidTypes, final boolean isOptional) {
         final List<String> types = Lists.newArrayList(validTypes);
-        Iterables.removeAll(types, invalidTypes);
+        if (invalidTypes != null && !invalidTypes.isEmpty()) {
+            Iterables.removeAll(types, invalidTypes);
+        }
         if(isOptional)
             return SGuiChoose.oneOrNone("Choose a " + kindOfType.toLowerCase() + " type", types);
         else