[40K] Implement Seeker of Slaanesh; added new must attack option (#12712)

* Add player-based "must attack" requirement check

* Implement Seeker of Slaanesh and add (ignored) test

* Fix check for ability of any controlled creatures to attack

* rename misleading variable

Mage.Server.Plugins/Mage.Player.Human/src/mage/player/human/HumanPlayer.java

@@ -1916,6 +1916,10 @@ public class HumanPlayer extends PlayerImpl {
         // check if enough attackers are declared
         // check if players have to be attacked
         Set<UUID> playersToAttackIfAble = new HashSet<>();
+        
+        // or if active player must attack with anything
+        boolean mustAttack = false;
+
         for (Map.Entry<RequirementEffect, Set<Ability>> entry : game.getContinuousEffects().getApplicableRequirementEffects(null, true, game).entrySet()) {
             RequirementEffect effect = entry.getKey();
             for (Ability ability : entry.getValue()) {
@@ -1923,6 +1927,9 @@ public class HumanPlayer extends PlayerImpl {
                 if (playerToAttack != null) {
                     playersToAttackIfAble.add(playerToAttack);
                 }
+                if (effect.mustAttack(game)){
+                    mustAttack = true;
+                }
             }
         }
         if (!playersToAttackIfAble.isEmpty()) {
@@ -1960,6 +1967,16 @@ public class HumanPlayer extends PlayerImpl {
             }
         }
 
+        if (mustAttack && game.getCombat().getAttackers().isEmpty()){
+            // no attackers, but required to attack with something -- check if anything can attack
+            for (Permanent attacker : game.getBattlefield().getAllActivePermanents(StaticFilters.FILTER_PERMANENT_CREATURE, getId(), game)) {
+                if (attacker.canAttackInPrinciple(null, game)){
+                    game.informPlayer(this, "You are forced to attack with at least one creature, e.g. " + attacker.getIdName() + ".");
+                    return false;
+                }
+            }
+        }
+
         return true;
     }
 

Mage.Sets/src/mage/cards/s/SeekerOfSlaanesh.java

@@ -0,0 +1,83 @@
+package mage.cards.s;
+
+import java.util.UUID;
+import mage.MageInt;
+import mage.abilities.Ability;
+import mage.abilities.common.SimpleStaticAbility;
+import mage.abilities.effects.RequirementEffect;
+import mage.constants.Duration;
+import mage.constants.SubType;
+import mage.abilities.keyword.HasteAbility;
+import mage.cards.CardImpl;
+import mage.cards.CardSetInfo;
+import mage.constants.CardType;
+import mage.constants.Zone;
+import mage.game.Game;
+import mage.game.permanent.Permanent;
+import mage.players.Player;
+
+/**
+ *
+ * @author jimga150
+ */
+public final class SeekerOfSlaanesh extends CardImpl {
+
+    public SeekerOfSlaanesh(UUID ownerId, CardSetInfo setInfo) {
+        super(ownerId, setInfo, new CardType[]{CardType.CREATURE}, "{3}{R}");
+        
+        this.subtype.add(SubType.DEMON);
+        this.power = new MageInt(3);
+        this.toughness = new MageInt(3);
+
+        // Haste
+        this.addAbility(HasteAbility.getInstance());
+
+        // Allure of Slaanesh -- Each opponent must attack with at least one creature each combat if able.
+        addAbility(new SimpleStaticAbility(Zone.BATTLEFIELD, new SeekerOfSlaaneshForceAttackEffect(Duration.WhileOnBattlefield))
+                .withFlavorWord("Allure of Slaanesh"));
+    }
+
+    private SeekerOfSlaanesh(final SeekerOfSlaanesh card) {
+        super(card);
+    }
+
+    @Override
+    public SeekerOfSlaanesh copy() {
+        return new SeekerOfSlaanesh(this);
+    }
+}
+
+// Based on TroveOfTemptationForceAttackEffect
+class SeekerOfSlaaneshForceAttackEffect extends RequirementEffect {
+
+    SeekerOfSlaaneshForceAttackEffect(Duration duration) {
+        super(duration, true);
+        staticText = "Each opponent must attack with at least one creature each combat if able.";
+    }
+
+    private SeekerOfSlaaneshForceAttackEffect(final SeekerOfSlaaneshForceAttackEffect effect) {
+        super(effect);
+    }
+
+    @Override
+    public SeekerOfSlaaneshForceAttackEffect copy() {
+        return new SeekerOfSlaaneshForceAttackEffect(this);
+    }
+
+    @Override
+    public boolean mustAttack(Game game) {
+        return true;
+    }
+
+    @Override
+    public boolean mustBlock(Game game) {
+        return false;
+    }
+
+    @Override
+    public boolean applies(Permanent permanent, Ability source, Game game) {
+        Player controller = game.getPlayer(source.getControllerId());
+        return controller != null && controller.hasOpponent(game.getActivePlayerId(), game);
+    }
+
+}

Mage.Sets/src/mage/sets/Warhammer40000.java

@@ -224,6 +224,7 @@ public final class Warhammer40000 extends ExpansionSet {
         cards.add(new SetCardInfo("Scoured Barrens", 293, Rarity.COMMON, mage.cards.s.ScouredBarrens.class));
         cards.add(new SetCardInfo("Screamer-Killer", 84, Rarity.RARE, mage.cards.s.ScreamerKiller.class));
         cards.add(new SetCardInfo("Sculpting Steel", 247, Rarity.RARE, mage.cards.s.SculptingSteel.class));
+        cards.add(new SetCardInfo("Seeker of Slaanesh", 85, Rarity.UNCOMMON, mage.cards.s.SeekerOfSlaanesh.class));
         cards.add(new SetCardInfo("Shadow in the Warp", 140, Rarity.RARE, mage.cards.s.ShadowInTheWarp.class));
         cards.add(new SetCardInfo("Shard of the Nightbringer", 55, Rarity.RARE, mage.cards.s.ShardOfTheNightbringer.class));
         cards.add(new SetCardInfo("Shard of the Void Dragon", 56, Rarity.RARE, mage.cards.s.ShardOfTheVoidDragon.class));

Mage.Tests/src/test/java/org/mage/test/AI/basic/AttackAndBlockByAITest.java

@@ -174,7 +174,7 @@ public class AttackAndBlockByAITest extends CardTestPlayerBaseAI {
     }
 
     @Test
-    @Ignore // TODO: need to fix Trove of Temptation effect (player must attack by one creature)
+    @Ignore // TODO: need to fix Trove of Temptation effect (player must be attacked by one creature)
     public void test_ForceAttack_1_small_vs_1_big_b() {
         addCard(Zone.BATTLEFIELD, playerA, "Arbor Elf", 1); // 1/1
         addCard(Zone.BATTLEFIELD, playerB, "Ancient Brontodon", 1); // 9/9
@@ -193,6 +193,24 @@ public class AttackAndBlockByAITest extends CardTestPlayerBaseAI {
         assertLife(playerB, 20);
     }
 
+    @Test
+    @Ignore // TODO: need to fix Seeker of Slaanesh effect (players must attack by one creature)
+    public void test_ForceAttack_any() {
+        addCard(Zone.BATTLEFIELD, playerA, "Arbor Elf", 1); // 1/1
+        // Each opponent must attack with at least one creature each combat if able.
+        addCard(Zone.BATTLEFIELD, playerB, "Seeker of Slaanesh", 1); // 3/3
+
+        block(1, playerB, "Seeker of Slaanesh", "Arbor Elf");
+
+        setStopAt(1, PhaseStep.END_TURN);
+        setStrictChooseMode(true);
+        execute();
+
+        assertGraveyardCount(playerA, "Arbor Elf", 1);
+        assertLife(playerA, 20);
+        assertLife(playerB, 20);
+    }
+
     @Test
     public void test_Attack_1_with_counters_vs_1() {
         // chainbreaker real stats is 1/1, it's can be saftly attacked