diff --git a/projects/mtg/include/Navigator.h b/projects/mtg/include/Navigator.h
index 30d238f86..eafa00bb3 100644
--- a/projects/mtg/include/Navigator.h
+++ b/projects/mtg/include/Navigator.h
@@ -16,7 +16,7 @@ class Navigator: public CardSelectorBase
 {
 public:
 
-    Navigator(DuelLayers* inDuelLayers);
+    Navigator(GameObserver *observer, DuelLayers* inDuelLayers);
     virtual ~Navigator();
 
     // Inherited functions from GuiLayer
diff --git a/projects/mtg/src/MTGGameZones.cpp b/projects/mtg/src/MTGGameZones.cpp
index 1ac2885cf..82bec0b06 100644
--- a/projects/mtg/src/MTGGameZones.cpp
+++ b/projects/mtg/src/MTGGameZones.cpp
@@ -426,7 +426,7 @@ MTGGameZone::MTGGameZone() :
 
 MTGGameZone::~MTGGameZone()
 {
-    for (int i = 0; i < cards.size(); i++)
+    for (size_t i = 0; i < cards.size(); i++)
     {
         SAFE_DELETE( cards[i] );
     }
diff --git a/projects/mtg/src/Navigator.cpp b/projects/mtg/src/Navigator.cpp
index b31d739fd..27a306766 100644
--- a/projects/mtg/src/Navigator.cpp
+++ b/projects/mtg/src/Navigator.cpp
@@ -382,8 +382,8 @@ CardZone* LandCardZone::EnterZone(JButton inDirection)
 /*
  ** Constructor.  All the navigation logic is initialized here, by pairing up each card zone with a set of neighbours.
  */
-Navigator::Navigator(DuelLayers* inDuelLayers) :
-    mDrawPosition(kDefaultCardPosition), mDuelLayers(inDuelLayers), mLimitorEnabled(false)
+Navigator::Navigator(GameObserver *observer, DuelLayers* inDuelLayers) :
+    CardSelectorBase(observer), mDrawPosition(kDefaultCardPosition), mDuelLayers(inDuelLayers), mLimitorEnabled(false)
 {
     assert(mDuelLayers);
 
@@ -500,10 +500,10 @@ bool Navigator::CheckUserInput(JButton inKey)
     switch (inKey)
     {
     case JGE_BTN_SEC:
-        GameObserver::GetInstance()->cancelCurrentAction();
+        observer->cancelCurrentAction();
         return true;
     case JGE_BTN_OK:
-        GameObserver::GetInstance()->ButtonPressed(GetCurrentCard());
+        observer->ButtonPressed(GetCurrentCard());
         return true;
         break;
     case JGE_BTN_LEFT:
diff --git a/projects/mtg/src/TestSuiteAI.cpp b/projects/mtg/src/TestSuiteAI.cpp
index 1e0cb12fd..e6079b482 100644
--- a/projects/mtg/src/TestSuiteAI.cpp
+++ b/projects/mtg/src/TestSuiteAI.cpp
@@ -291,7 +291,7 @@ MTGPlayerCards * TestSuite::buildDeck(Player* player, int playerId)
 
         for (int j = 0; j < 4; j++)
         {
-            for (int k = 0; k < loadedPlayerZones[j]->cards.size(); k++)
+            for (size_t k = 0; k < loadedPlayerZones[j]->cards.size(); k++)
             {
                 int cardid = loadedPlayerZones[j]->cards[k]->getId();
                 list[nbcards] = cardid;
@@ -338,7 +338,7 @@ void TestSuite::initGame(GameObserver* g)
         for (int j = 0; j < 4; j++)
         {
             MTGGameZone * zone = playerZones[j];
-            for (int k = 0; k < loadedPlayerZones[j]->cards.size(); k++)
+            for (size_t k = 0; k < loadedPlayerZones[j]->cards.size(); k++)
             {
                 MTGCardInstance * card = Rules::getCardByMTGId(g, loadedPlayerZones[j]->cards[k]->getId());
                 if (card && zone != p->game->library)
@@ -348,7 +348,7 @@ void TestSuite::initGame(GameObserver* g)
                         MTGCardInstance * copy = p->game->putInZone(card, p->game->library, p->game->stack);
                         Spell * spell = NEW Spell(g, copy);
                         spell->resolve();
-                        if (!summoningSickness && p->game->inPlay->nb_cards > k) p->game->inPlay->cards[k]->summoningSickness = 0;
+                        if (!summoningSickness && (size_t)p->game->inPlay->nb_cards > k) p->game->inPlay->cards[k]->summoningSickness = 0;
                         delete spell;
                     }
                     else
@@ -457,7 +457,7 @@ int TestSuite::assertGame(GameObserver* g)
                 Log(result);
                 error++;
             }
-            for (int k = 0; k < endstateZones[j]->nb_cards; k++)
+            for (size_t k = 0; k < (size_t)endstateZones[j]->nb_cards; k++)
             {
                 MTGCardInstance* cardToCheck = (k<endstateZones[j]->cards.size())?endstateZones[j]->cards[k]:0;
                 if(cardToCheck)