Try to keep original card and not migrate to new card

forge-game/src/main/java/forge/game/GameAction.java

@@ -338,13 +338,10 @@ public class GameAction {
         }
 
         // update state for view
-        copied.updateStateForView();
         if (copied.isMerged()) {
-            if (copied.getMergedToCard() != null) {
-                copied.getMergedToCard().updateStateForView();
-            } else {
-                copied.getMergedCards().get(0).updateStateForView();
-            }
+            copied.getMergedToCard().updateStateForView();
+        } else {
+            copied.updateStateForView();
         }
 
         if (fromBattlefield) {

forge-game/src/main/java/forge/game/ability/effects/MutateEffect.java

@@ -47,17 +47,17 @@ public class MutateEffect extends SpellAbilityEffect {
         );
         final boolean putOnTop = (topCard == host);
 
+        host.setMergedToCard(target);
+        // If first time mutate, add target first.
+        if (target.getMergedCards().isEmpty()) {
+            target.addMergedCard(target);
+        }
         if (putOnTop) {
-            host.addMergedCard(target);
-            host.addMergedCards(target.getMergedCards());
-            target.clearMergedCards();
-            target.setMergedToCard(host);
+            target.addMergedCardToTop(host);
         } else {
             target.addMergedCard(host);
-            host.setMergedToCard(target);
         }
 
-
         // First remove current mutated states
         if (target.getMutatedTimestamp() != -1) {
             target.removeCloneState(target.getMutatedTimestamp());
@@ -66,27 +66,21 @@ public class MutateEffect extends SpellAbilityEffect {
         // Now add all abilities from bottom cards
         final Long ts = game.getNextTimestamp();
         if (topCard.getCurrentStateName() != CardStateName.FaceDown) {
-            final CardCloneStates mutatedStates = CardFactory.getMutatedCloneStates(topCard, sa);
-            topCard.addCloneState(mutatedStates, ts);
-            topCard.setMutatedTimestamp(ts);
-        }
-        if (topCard == target) {
-            // Re-register triggers for target card
-            game.getTriggerHandler().clearActiveTriggers(target, null);
-            game.getTriggerHandler().registerActiveTrigger(target, false);
+            final CardCloneStates mutatedStates = CardFactory.getMutatedCloneStates(target, sa);
+            target.addCloneState(mutatedStates, ts);
+            target.setMutatedTimestamp(ts);
         }
+        // Re-register triggers for target card
+        game.getTriggerHandler().clearActiveTriggers(target, null);
+        game.getTriggerHandler().registerActiveTrigger(target, false);
 
         game.getAction().moveToPlay(host, p, sa);
 
-        if (topCard == host) {
-            CardFactory.migrateTopCard(host, target);
-        } else {
-            host.setTapped(target.isTapped());
-            host.setFlipped(target.isFlipped());
-        }
-        topCard.setTimesMutated(topCard.getTimesMutated() + 1);
+        host.setTapped(target.isTapped());
+        host.setFlipped(target.isFlipped());
+        target.setTimesMutated(target.getTimesMutated() + 1);
 
-        game.getTriggerHandler().runTrigger(TriggerType.Mutates, AbilityKey.mapFromCard(topCard), false);
+        game.getTriggerHandler().runTrigger(TriggerType.Mutates, AbilityKey.mapFromCard(target), false);
     }
 
 }

forge-game/src/main/java/forge/game/card/Card.java

@@ -1010,8 +1010,9 @@ public class Card extends GameEntity implements Comparable<Card>, IHasSVars {
     public final void addMergedCard(final Card c) {
         mergedCards = view.addCard(mergedCards, c, TrackableProperty.MergedCards);
     }
-    public final void addMergedCards(final Iterable<Card> cards) {
-        mergedCards = view.addCards(mergedCards, cards, TrackableProperty.MergedCards);
+    public final void addMergedCardToTop(final Card c) {
+        mergedCards.add(0, c);
+        view.setCards(mergedCards, mergedCards, TrackableProperty.MergedCards);
     }
     public final void removeMergedCard(final Card c) {
         mergedCards = view.removeCard(mergedCards, c, TrackableProperty.MergedCards);
@@ -1028,7 +1029,7 @@ public class Card extends GameEntity implements Comparable<Card>, IHasSVars {
     }
 
     public final boolean isMerged() {
-        return !getMergedCards().isEmpty() || getMergedToCard() != null;
+        return getMergedToCard() != null;
     }
 
     public final boolean isMutated() {
@@ -3740,9 +3741,6 @@ public class Card extends GameEntity implements Comparable<Card>, IHasSVars {
         if (tapped == tapped0) { return; }
         tapped = tapped0;
         view.updateTapped(this);
-        for (final Card c : getMergedCards()) {
-            c.setTapped(tapped0);
-        }
     }
 
     public final void tap() {

forge-game/src/main/java/forge/game/card/CardFactory.java

@@ -823,49 +823,23 @@ public class CardFactory {
     }
 
     public static CardCloneStates getMutatedCloneStates(final Card card, final CardTraitBase sa) {
-        final CardStateName state = card.getCurrentStateName();
+        final Card top = card.getMergedCards().get(0);
+        final CardStateName state = top.getCurrentStateName();
         final CardState ret = new CardState(card, state);
-        ret.copyFrom(card.getState(state, true), false);
+        ret.copyFrom(top.getState(state, true), false);
 
+        boolean first = true;
         for (final Card c : card.getMergedCards()) {
+            if (first) {
+                first = false;
+                continue;
+            }
             ret.addAbilitiesFrom(c.getCurrentState(), false);
         }
 
-        final CardCloneStates result = new CardCloneStates(card, sa);
+        final CardCloneStates result = new CardCloneStates(top, sa);
         result.put(state, ret);
         return result;
     }
 
-    public static void migrateTopCard(final Card host, final Card target) {
-        // Copy all status from target card and migrate all counters
-        // Also update all reference of target card to new top card
-
-        // TODO: find out all necessary status that should be copied
-        host.setTapped(target.isTapped());
-        host.setSickness(target.isFirstTurnControlled());
-        host.setFlipped(target.isFlipped());
-        host.setDamage(target.getDamage());
-        host.setTimesMutated(target.getTimesMutated());
-        host.setMonstrous(target.isMonstrous());
-        host.setRenowned(target.isRenowned());
-
-        // Migrate counters
-        Map<CounterType, Integer> counters = target.getCounters();
-        if (!counters.isEmpty()) {
-            host.setCounters(Maps.newHashMap(counters));
-        }
-        target.clearCounters();
-
-        // Migrate attached cards
-        CardCollectionView attached = target.getAttachedCards();
-        for (final Card c : attached) {
-            c.setEntityAttachedTo(host);
-        }
-        target.setAttachedCards(null);
-        host.setAttachedCards(attached);
-
-        // TODO: move all remembered, imprinted objects to new top card
-        //       and possibly many other needs to be migrated.
-    }
-
 } // end class AbstractCardFactory

forge-game/src/main/java/forge/game/player/PlayerView.java

@@ -470,7 +470,7 @@ public class PlayerView extends GameEntityView {
     void updateZone(PlayerZone zone) {
         TrackableProperty prop = getZoneProp(zone.getZoneType());
         if (prop == null) { return; }
-        set(prop, CardView.getCollection(zone.getCards(false, false)));
+        set(prop, CardView.getCollection(zone.getCards(false, true)));
 
         //update delirium
         if (ZoneType.Graveyard == zone.getZoneType())