diff --git a/Mage.Server/src/main/java/mage/server/Session.java b/Mage.Server/src/main/java/mage/server/Session.java
index 018e6b4a1a3..e908f8898bb 100644
--- a/Mage.Server/src/main/java/mage/server/Session.java
+++ b/Mage.Server/src/main/java/mage/server/Session.java
@@ -66,6 +66,7 @@ public class Session {
     private final Date timeConnected;
     private boolean isAdmin = false;
     private final AsynchInvokerCallbackHandler callbackHandler;
+    private boolean error = false;
 
     private final ReentrantLock lock;
 
@@ -370,10 +371,14 @@ public class Session {
     }
 
     public void fireCallback(final ClientCallback call) {
+        if (error) {
+            return;
+        }
         try {
             call.setMessageId(messageId++);
             callbackHandler.handleCallbackOneway(new Callback(call));
         } catch (HandleCallbackException ex) {
+            error = true; // to reduce repeated SESSION CALLBACK EXCEPTION
             UserManager.instance.getUser(userId).ifPresent(user -> {
                 user.setUserState(User.UserState.Disconnected);
                 logger.warn("SESSION CALLBACK EXCEPTION - " + user.getName() + " userId " + userId + " - cause: " + getBasicCause(ex).toString());
diff --git a/Mage.Server/src/main/java/mage/server/User.java b/Mage.Server/src/main/java/mage/server/User.java
index e1f0abd8fd5..37da6692ba5 100644
--- a/Mage.Server/src/main/java/mage/server/User.java
+++ b/Mage.Server/src/main/java/mage/server/User.java
@@ -358,14 +358,16 @@ public class User {
         for (Entry<UUID, Table> entry : tables.entrySet()) {
             ccJoinedTable(entry.getValue().getRoomId(), entry.getValue().getId(), entry.getValue().isTournament());
         }
-        for (Entry<UUID, UUID> entry : userTournaments.entrySet()) {
-            TournamentController tournamentController = TournamentManager.instance.getTournamentController(entry.getValue());
+        for (Iterator<Entry<UUID, UUID>> iterator = userTournaments.entrySet().iterator(); iterator.hasNext();) {
+            Entry<UUID, UUID> next = iterator.next();
+            TournamentController tournamentController = TournamentManager.instance.getTournamentController(next.getValue());
             if (tournamentController != null) {
-                ccTournamentStarted(entry.getValue(), entry.getKey());
-                tournamentController.rejoin(entry.getKey());
+                ccTournamentStarted(next.getValue(), next.getKey());
+                tournamentController.rejoin(next.getKey());
+            } else {
+                iterator.remove(); // tournament has ended meanwhile
             }
         }
-
         for (Entry<UUID, GameSessionPlayer> entry : gameSessions.entrySet()) {
             ccGameStarted(entry.getValue().getGameId(), entry.getKey());
             entry.getValue().init();
diff --git a/Mage.Sets/src/mage/cards/e/EternalDominion.java b/Mage.Sets/src/mage/cards/e/EternalDominion.java
index 9ae0fd09d98..7c7c777d81e 100644
--- a/Mage.Sets/src/mage/cards/e/EternalDominion.java
+++ b/Mage.Sets/src/mage/cards/e/EternalDominion.java
@@ -53,14 +53,15 @@ import mage.target.common.TargetOpponent;
 public class EternalDominion extends CardImpl {
 
     public EternalDominion(UUID ownerId, CardSetInfo setInfo) {
-        super(ownerId,setInfo,new CardType[]{CardType.SORCERY},"{7}{U}{U}{U}");
+        super(ownerId, setInfo, new CardType[]{CardType.SORCERY}, "{7}{U}{U}{U}");
 
         // Search target opponent's library for an artifact, creature, enchantment, or land card.
         // Put that card onto the battlefield under your control. Then that player shuffles his or her library.
         this.getSpellAbility().addEffect(new EternalDominionEffect());
         this.getSpellAbility().addTarget(new TargetOpponent());
 
-        // Epic
+        // Epic (For the rest of the game, you can't cast spells. At the beginning of each of your upkeeps
+        // for the rest of the game, copy this spell except for its epic ability. If the spell has targets, you may choose new targets for the copy)
         this.getSpellAbility().addEffect(new EpicEffect());
 
     }
diff --git a/Mage.Sets/src/mage/cards/p/PathOfMettle.java b/Mage.Sets/src/mage/cards/p/PathOfMettle.java
index c8242bb6c2b..93bd1198ed2 100644
--- a/Mage.Sets/src/mage/cards/p/PathOfMettle.java
+++ b/Mage.Sets/src/mage/cards/p/PathOfMettle.java
@@ -126,13 +126,15 @@ class PathOfMettleTriggeredAbility extends TriggeredAbilityImpl {
     @Override
     public boolean checkTrigger(GameEvent event, Game game) {
         int attackerCount = 0;
-        if (game.getCombat().getAttackingPlayerId().equals(getControllerId())) {
-            for (UUID attacker : game.getCombat().getAttackers()) {
-                if (filter.match(game.getPermanent(attacker), game)) {
-                    attackerCount++;
+        if (game.getCombat() != null) {
+            if (getControllerId().equals(game.getCombat().getAttackingPlayerId())) {
+                for (UUID attacker : game.getCombat().getAttackers()) {
+                    if (filter.match(game.getPermanent(attacker), game)) {
+                        attackerCount++;
+                    }
                 }
+                return attackerCount >= 2;
             }
-            return attackerCount >= 2;
         }
         return false;
 
diff --git a/Mage/src/main/java/mage/abilities/effects/common/AttachEffect.java b/Mage/src/main/java/mage/abilities/effects/common/AttachEffect.java
index efe93399ea8..9716c790aa7 100644
--- a/Mage/src/main/java/mage/abilities/effects/common/AttachEffect.java
+++ b/Mage/src/main/java/mage/abilities/effects/common/AttachEffect.java
@@ -74,7 +74,7 @@ public class AttachEffect extends OneShotEffect {
                     if (player != null) {
                         return player.addAttachment(source.getSourceId(), game);
                     }
-                    if (source.getTargets().get(0) instanceof TargetCard) { // e.g. Spellweaver Volute
+                    if (!source.getTargets().isEmpty() && source.getTargets().get(0) instanceof TargetCard) { // e.g. Spellweaver Volute
                         Card card = game.getCard(getTargetPointer().getFirst(game, source));
                         if (card != null) {
                             return card.addAttachment(source.getSourceId(), game);
diff --git a/Mage/src/main/java/mage/game/match/MatchImpl.java b/Mage/src/main/java/mage/game/match/MatchImpl.java
index 961996df324..caccd3e463c 100644
--- a/Mage/src/main/java/mage/game/match/MatchImpl.java
+++ b/Mage/src/main/java/mage/game/match/MatchImpl.java
@@ -433,7 +433,9 @@ public abstract class MatchImpl implements Match {
                 sb.append(" QUITTED");
             }
             sb.append("<br/>");
-            sb.append("DeckHash: ").append(mp.getDeck().getDeckHashCode()).append("<br/>");
+            if (mp.getDeck() != null) {
+                sb.append("DeckHash: ").append(mp.getDeck().getDeckHashCode()).append("<br/>");
+            }
         }
         if (getDraws() > 0) {
             sb.append("   Draws: ").append(getDraws()).append("<br/>");
diff --git a/Mage/src/main/java/mage/players/PlayerImpl.java b/Mage/src/main/java/mage/players/PlayerImpl.java
index a0723b0ba5f..b28ba370b57 100644
--- a/Mage/src/main/java/mage/players/PlayerImpl.java
+++ b/Mage/src/main/java/mage/players/PlayerImpl.java
@@ -53,7 +53,6 @@ import mage.cards.Card;
 import mage.cards.Cards;
 import mage.cards.CardsImpl;
 import mage.cards.SplitCard;
-import mage.cards.SplitCardHalf;
 import mage.cards.decks.Deck;
 import mage.choices.ChoiceImpl;
 import mage.constants.*;
@@ -858,9 +857,11 @@ public abstract class PlayerImpl implements Player, Serializable {
             Cards cards = new CardsImpl(cardsToLibrary); // prevent possible ConcurrentModificationException
             if (!anyOrder) {
                 while (!cards.isEmpty()) {
-                    UUID cardId = cards.getRandom(game).getId();
-                    cards.remove(cardId);
-                    moveObjectToLibrary(cardId, source == null ? null : source.getSourceId(), game, false, false);
+                    Card card = cards.getRandom(game);
+                    if (card != null) {
+                        cards.remove(card);
+                        moveObjectToLibrary(card.getId(), source == null ? null : source.getSourceId(), game, false, false);
+                    }
                 }
             } else {
                 TargetCard target = new TargetCard(Zone.ALL, new FilterCard("card to put on the bottom of your library (last one chosen will be bottommost)"));
@@ -1866,7 +1867,7 @@ public abstract class PlayerImpl implements Player, Serializable {
                             player.gainLife(actualDamage, game);
                         }
                         // Unstable ability - Earl of Squirrel
-                        if (sourceAbilities.containsKey(SquirrellinkAbility.getInstance().getId())) {
+                        if (sourceAbilities != null && sourceAbilities.containsKey(SquirrellinkAbility.getInstance().getId())) {
                             Player player = game.getPlayer(sourceControllerId);
                             new SquirrelToken().putOntoBattlefield(actualDamage, game, sourceId, player.getId());
                         }