refactor SavedGainedLifeValue instead of getValue("gainedLife")

Mage/src/main/java/mage/abilities/common/GainLifeControllerTriggeredAbility.java

@@ -1,6 +1,7 @@
 package mage.abilities.common;
 
 import mage.abilities.TriggeredAbilityImpl;
+import mage.abilities.dynamicvalue.common.SavedGainedLifeValue;
 import mage.abilities.effects.Effect;
 import mage.constants.Zone;
 import mage.game.Game;
@@ -46,7 +47,7 @@ public class GainLifeControllerTriggeredAbility extends TriggeredAbilityImpl {
     @Override
     public boolean checkTrigger(GameEvent event, Game game) {
         if (event.getPlayerId().equals(this.getControllerId())) {
-            this.getEffects().setValue("gainedLife", event.getAmount());
+            this.getEffects().setValue(SavedGainedLifeValue.VALUE_KEY, event.getAmount());
             if (setTargetPointer) {
                 this.getEffects().setTargetPointer(new FixedTarget(event.getPlayerId()));
             }

Mage/src/main/java/mage/abilities/dynamicvalue/common/SavedGainedLifeValue.java

@@ -0,0 +1,45 @@
+package mage.abilities.dynamicvalue.common;
+
+import mage.abilities.Ability;
+import mage.abilities.dynamicvalue.DynamicValue;
+import mage.abilities.effects.Effect;
+import mage.game.Game;
+
+import java.util.Optional;
+
+/**
+ * Stores gained life value in relevant triggers, to pass down on effects.
+ *
+ * @author Susucr
+ */
+public enum SavedGainedLifeValue implements DynamicValue {
+    MANY("many"),
+    MUCH("much");
+
+    private final String message;
+    public static final String VALUE_KEY = "gainedLife";
+
+    SavedGainedLifeValue(String message) {
+        this.message = "that " + message;
+    }
+
+    @Override
+    public int calculate(Game game, Ability sourceAbility, Effect effect) {
+        return Optional.ofNullable((Integer) effect.getValue(VALUE_KEY)).orElse(0);
+    }
+
+    @Override
+    public SavedGainedLifeValue copy() {
+        return this;
+    }
+
+    @Override
+    public String toString() {
+        return message;
+    }
+
+    @Override
+    public String getMessage() {
+        return "";
+    }
+}

Mage/src/main/java/mage/abilities/effects/common/counter/AddCountersSourceEffect.java

@@ -35,6 +35,10 @@ public class AddCountersSourceEffect extends OneShotEffect {
         this(counter, StaticValue.get(0), informPlayers);
     }
 
+    public AddCountersSourceEffect(Counter counter, DynamicValue amount) {
+        this(counter, amount, true);
+    }
+
     public AddCountersSourceEffect(Counter counter, DynamicValue amount, boolean informPlayers) {
         this(counter, amount, informPlayers, false);
     }