you can't pay life which you do not have as life payments.

projects/mtg/include/ExtraCost.h

@@ -57,7 +57,7 @@ public:
 class LifeCost: public ExtraCost{
 public:
   LifeCost(TargetChooser *_tc = NULL);
-
+  virtual int canPay();
   virtual int doPay();
   virtual LifeCost * clone() const;
 };
@@ -66,6 +66,7 @@ class LifeorManaCost: public ExtraCost{
 public:
     LifeorManaCost(TargetChooser *_tc = NULL,string manaType = "");
     string manaType;
+    virtual int canPay();
     virtual int doPay();
     virtual LifeorManaCost * clone() const;
 };

projects/mtg/src/ExtraCost.cpp

@@ -74,6 +74,16 @@ LifeCost::LifeCost(TargetChooser *_tc) :
 {
 }
 
+    int LifeCost::canPay()
+    {
+        MTGCardInstance * _target = (MTGCardInstance *) target;
+        if(_target->controller()->life <= 0)
+        {
+            return 0;
+        }
+        return 1;
+    }
+
 int LifeCost::doPay()
 {
     if (!target)
@@ -101,6 +111,16 @@ LifeorManaCost::LifeorManaCost(TargetChooser *_tc,string manaType) :
 {
 }
 
+    int LifeorManaCost::canPay()
+    {
+        MTGCardInstance * _target = (MTGCardInstance *) target;
+        if(_target->controller()->life <= 0)
+        {
+            return 0;
+        }
+        return 1;
+    }
+
 int LifeorManaCost::doPay()
 {
     if (!target)

projects/mtg/src/GameObserver.cpp

@@ -487,7 +487,7 @@ void GameObserver::gameStateBasedEffects()
             for (int j = 0; j < nbcards; ++j)
             {
                 MTGCardInstance * c = z->cards[j];
-                if (c->has(Constants::CANTLOSE) || (c->has(Constants::CANTLIFELOSE && players[i]->poisonCount < 10)))
+                if (c->has(Constants::CANTLOSE) || (c->has(Constants::CANTLIFELOSE) && players[i]->poisonCount < 10))
                 {
                     cantlosers++;
                 }