diff --git a/forge-ai/src/main/java/forge/ai/AiController.java b/forge-ai/src/main/java/forge/ai/AiController.java
index 2c761044964..97943fe1750 100644
--- a/forge-ai/src/main/java/forge/ai/AiController.java
+++ b/forge-ai/src/main/java/forge/ai/AiController.java
@@ -1483,23 +1483,25 @@ public class AiController {
         
         boolean hasLeyline1 = false;
         SpellAbility saGemstones = null;
-        
-        for(int i = 0; i < result.size(); i++) {
-            SpellAbility sa = result.get(i);
-            
+
+        List<SpellAbility> toRemove = Lists.newArrayList();
+        for(SpellAbility sa : result) {
             String srcName = sa.getHostCard().getName();
             if ("Gemstone Caverns".equals(srcName)) {
                 if (saGemstones == null)
                     saGemstones = sa;
                 else
-                    result.remove(i--);
+                    toRemove.add(sa);
             } else if ("Leyline of Singularity".equals(srcName)) {
                 if (!hasLeyline1)
                     hasLeyline1 = true;
                 else
-                    result.remove(i--);
+                    toRemove.add(sa);
             }
         }
+        for(SpellAbility sa : toRemove) {
+            result.remove(sa);
+        }
         
         // Play them last
         if (saGemstones != null) {
diff --git a/forge-game/src/main/java/forge/game/GameAction.java b/forge-game/src/main/java/forge/game/GameAction.java
index 2741c83f892..be3959b2ac7 100644
--- a/forge-game/src/main/java/forge/game/GameAction.java
+++ b/forge-game/src/main/java/forge/game/GameAction.java
@@ -798,16 +798,18 @@ public class GameAction {
             public boolean visit(final Card c) {
                 // need to get Card from preList if able
                 final Card co = preList.get(c);
-                for (int i = 0; i < co.getStaticAbilities().size(); i++) {
-                    final StaticAbility stAb = co.getStaticAbilities().get(i);
+                List<StaticAbility> toRemove = Lists.newArrayList();
+                for (StaticAbility stAb : co.getStaticAbilities()) {
                     if (stAb.getMapParams().get("Mode").equals("Continuous")) {
                         staticAbilities.add(stAb);
                     }
                     if (stAb.isTemporary()) {
-                        co.removeStaticAbility(stAb);
-                        i--;
+                        toRemove.add(stAb);
                     }
                  }
+                 for (StaticAbility stAb : toRemove) {
+                     co.removeStaticAbility(stAb);
+                 }
                  if (!co.getStaticCommandList().isEmpty()) {
                      staticList.add(co);
                  }
@@ -851,8 +853,8 @@ public class GameAction {
         }
 
         for (final Card c : staticList) {
-            for (int i = 0; i < c.getStaticCommandList().size(); i++) {
-                final Object[] staticCheck = c.getStaticCommandList().get(i);
+            List<Object[]> toRemove = Lists.newArrayList();
+            for (Object[] staticCheck : c.getStaticCommandList()) {
                 final String leftVar = (String) staticCheck[0];
                 final String rightVar = (String) staticCheck[1];
                 final Card affected = (Card) staticCheck[2];
@@ -863,11 +865,13 @@ public class GameAction {
                 final int operandValue = AbilityUtils.calculateAmount(c, svarOperand, null);
                 if (Expressions.compare(sVar, svarOperator, operandValue)) {
                     ((GameCommand) staticCheck[3]).run();
-                    c.getStaticCommandList().remove(i);
-                    i--;
+                    toRemove.add(staticCheck);
                     affectedCards.add(c);
                 }
             }
+            for (Object[] staticCheck : c.getStaticCommandList()) {
+                c.getStaticCommandList().remove(staticCheck);
+            }
         }
         // Exclude cards in hidden zones from update
         Iterator<Card> it = affectedCards.iterator();
diff --git a/forge-game/src/main/java/forge/game/replacement/ReplacementHandler.java b/forge-game/src/main/java/forge/game/replacement/ReplacementHandler.java
index c47dd86d932..b1843c1850d 100644
--- a/forge-game/src/main/java/forge/game/replacement/ReplacementHandler.java
+++ b/forge-game/src/main/java/forge/game/replacement/ReplacementHandler.java
@@ -309,13 +309,15 @@ public class ReplacementHandler {
         game.forEachCardInGame(new Visitor<Card>() {
             @Override
             public boolean visit(Card c) {
-                for (int i = 0; i < c.getReplacementEffects().size(); i++) {
-                    ReplacementEffect rep = c.getReplacementEffects().get(i);
+                List<ReplacementEffect> toRemove = Lists.newArrayList();
+                for (ReplacementEffect rep : c.getReplacementEffects()) {
                     if (rep.isTemporary()) {
-                        c.removeReplacementEffect(rep);
-                        i--;
+                        toRemove.add(rep);
                     }
                 }
+                for (ReplacementEffect rep : toRemove) {
+                    c.removeReplacementEffect(rep);
+                }
                 return true;
             }
         });