Added Norn's Decree (#10281)

* Added Norn's Decree

Also added a couple of helper classes:
- A triggered ability for when players attack
- A triggered ability for the controller taking combat damage from one or more creatures (will be used in Starscream, Power Hungry)
- A condition for when an attacked player is poisoned

* Fixed rules comment issue

* Fixed issue with incorrect logic in CombatDamageDealtToYouTriggeredAbility

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

@@ -0,0 +1,87 @@
+package mage.abilities.common;
+
+import mage.abilities.TriggeredAbilityImpl;
+import mage.abilities.effects.Effect;
+import mage.constants.Zone;
+import mage.game.Game;
+import mage.game.events.DamagedPlayerEvent;
+import mage.game.events.GameEvent;
+import mage.target.targetpointer.FixedTarget;
+
+/**
+ * A triggered ability for whenever a player attacks. Has an optional component
+ * for setting the target pointer on effects to that attacking player.
+ * 
+ * @author alexander-novo
+ */
+public class PlayerAttacksTriggeredAbility extends TriggeredAbilityImpl {
+
+    // Whether or not the ability should set a target targetting the player who
+    // attacked
+    private final boolean setTarget;
+
+    /**
+     * @param effect The effect that should happen when the ability resolves
+     */
+    public PlayerAttacksTriggeredAbility(Effect effect) {
+        this(effect, false);
+    }
+
+    /**
+     * @param effect    The effect that should happen when the ability resolves
+     * @param setTarget Whether or not the ability should set a target targetting
+     *                  the player who attacked
+     */
+    public PlayerAttacksTriggeredAbility(Effect effect, boolean setTarget) {
+        this(Zone.BATTLEFIELD, effect, setTarget, false);
+    }
+
+    /**
+     * @param zone      Which zone the ability shoudl take effect in
+     * @param effect    The effect that should happen when the ability resolves
+     * @param setTarget Whether or not the ability should set a target targetting
+     *                  the player who attacked
+     * @param optional  Whether or not the ability is optional
+     */
+    public PlayerAttacksTriggeredAbility(Zone zone, Effect effect, boolean setTarget,
+            boolean optional) {
+        super(zone, effect, optional);
+
+        this.setTarget = setTarget;
+
+        setTriggerPhrase(generateTriggerPhrase());
+    }
+
+    private PlayerAttacksTriggeredAbility(final PlayerAttacksTriggeredAbility ability) {
+        super(ability);
+
+        this.setTarget = ability.setTarget;
+    }
+
+    @Override
+    public boolean checkEventType(GameEvent event, Game game) {
+        return event.getType() == GameEvent.EventType.DECLARED_ATTACKERS;
+    }
+
+    @Override
+    public boolean checkTrigger(GameEvent event, Game game) {
+        if (!game.getCombat().getAttackers().isEmpty()) {
+            if (this.setTarget) {
+                this.getEffects().setTargetPointer(
+                        new FixedTarget(event.getPlayerId()));
+            }
+            return true;
+        }
+
+        return false;
+    }
+
+    private String generateTriggerPhrase() {
+        return "Whenever a player attacks, ";
+    }
+
+    @Override
+    public PlayerAttacksTriggeredAbility copy() {
+        return new PlayerAttacksTriggeredAbility(this);
+    }
+}