- The AI will now be aware of opponents Royal Assassin and similar cards.

forge-ai/src/main/java/forge/ai/AiAttackController.java

@@ -973,7 +973,15 @@ public class AiAttackController {
                 }
             }
         }
-        if (ComputerUtilCard.canBeBlockedProfitably(defendingOpponent, attacker)) {
+        
+        if (!attacker.hasKeyword("vigilance") && ComputerUtilCard.canBeKilledByRoyalAssassin(ai, attacker)) {
+            canKillAllDangerous = false;
+            canBeKilled = true;
+            canBeKilledByOne = true;
+            isWorthLessThanAllKillers = false;
+            hasCombatEffect = false;
+        }
+        else if (ComputerUtilCard.canBeBlockedProfitably(defendingOpponent, attacker)) {
             canKillAllDangerous = false;
             canBeKilled = true;
         } 

forge-ai/src/main/java/forge/ai/ComputerUtilCard.java

@@ -14,6 +14,7 @@ import forge.deck.Deck;
 import forge.deck.DeckSection;
 import forge.game.Game;
 import forge.game.ability.AbilityUtils;
+import forge.game.ability.ApiType;
 import forge.game.card.*;
 import forge.game.combat.Combat;
 import forge.game.combat.CombatUtil;
@@ -593,6 +594,35 @@ public class ComputerUtilCard {
         return combat.isAttacking(card);
     }
 
+    public static boolean canBeKilledByRoyalAssassin(final Player ai, final Card card) {
+    	boolean wasTapped = card.isTapped();
+    	for (Player opp : ai.getOpponents()) {
+    		for (Card c : opp.getCardsIn(ZoneType.Battlefield)) {
+    			for (SpellAbility sa : c.getSpellAbilities()) {
+                    if (sa.getApi() != ApiType.Destroy) {
+                        continue;
+                    }
+                    if (!ComputerUtilCost.canPayCost(sa, opp)) {
+                        continue;
+                    }
+                    sa.setActivatingPlayer(opp);
+                    if (sa.canTarget(card)) {
+                    	continue;
+                    }
+                    // check whether the ability can only target tapped creatures
+                	card.setTapped(true);
+                    if (!sa.canTarget(card)) {
+                    	card.setTapped(wasTapped);
+                    	continue;
+                    }
+                	card.setTapped(wasTapped);
+                    return true;
+    			}
+    		}
+    	}
+    	return false;
+    }
+    
     /**
      * Create a mock combat and returns the list of likely blockers. 
      * @param ai blocking player