Redesigned handling of attack allowed check related to the complete attack.

Mage/src/main/java/mage/abilities/effects/RestrictionEffect.java

@@ -69,6 +69,10 @@ public abstract class RestrictionEffect extends ContinuousEffectImpl {
         return true;
     }
 
+    public boolean canAttackCheckAfter(int numberOfAttackers, Ability source, Game game) {
+        return true;
+    }
+
     public boolean canBlock(Permanent attacker, Permanent blocker, Ability source, Game game) {
         return true;
     }

Mage/src/main/java/mage/abilities/effects/common/combat/CanAttackOnlyAloneEffect.java

@@ -0,0 +1,43 @@
+/*
+ * To change this license header, choose License Headers in Project Properties.
+ * To change this template file, choose Tools | Templates
+ * and open the template in the editor.
+ */
+package mage.abilities.effects.common.combat;
+
+import mage.abilities.Ability;
+import mage.abilities.effects.RestrictionEffect;
+import mage.constants.Duration;
+import mage.game.Game;
+import mage.game.permanent.Permanent;
+
+/**
+ *
+ * @author LevelX2
+ */
+public class CanAttackOnlyAloneEffect extends RestrictionEffect {
+
+    public CanAttackOnlyAloneEffect() {
+        super(Duration.WhileOnBattlefield);
+        staticText = "{this} can only attack alone";
+    }
+
+    public CanAttackOnlyAloneEffect(final CanAttackOnlyAloneEffect effect) {
+        super(effect);
+    }
+
+    @Override
+    public CanAttackOnlyAloneEffect copy() {
+        return new CanAttackOnlyAloneEffect(this);
+    }
+
+    @Override
+    public boolean canAttackCheckAfter(int numberOfAttackers, Ability source, Game game) {
+        return numberOfAttackers == 1;
+    }
+
+    @Override
+    public boolean applies(Permanent permanent, Ability source, Game game) {
+        return source.getSourceId().equals(permanent.getId());
+    }
+}

Mage/src/main/java/mage/abilities/effects/common/combat/CantAttackAloneEffect.java

@@ -0,0 +1,43 @@
+/*
+ * To change this license header, choose License Headers in Project Properties.
+ * To change this template file, choose Tools | Templates
+ * and open the template in the editor.
+ */
+package mage.abilities.effects.common.combat;
+
+import mage.abilities.Ability;
+import mage.abilities.effects.RestrictionEffect;
+import mage.constants.Duration;
+import mage.game.Game;
+import mage.game.permanent.Permanent;
+
+/**
+ *
+ * @author LevelX2
+ */
+public class CantAttackAloneEffect extends RestrictionEffect {
+
+    public CantAttackAloneEffect() {
+        super(Duration.WhileOnBattlefield);
+        staticText = "{this} can't attack alone";
+    }
+
+    public CantAttackAloneEffect(final CantAttackAloneEffect effect) {
+        super(effect);
+    }
+
+    @Override
+    public CantAttackAloneEffect copy() {
+        return new CantAttackAloneEffect(this);
+    }
+
+    @Override
+    public boolean canAttackCheckAfter(int numberOfAttackers, Ability source, Game game) {
+        return numberOfAttackers > 1;
+    }
+
+    @Override
+    public boolean applies(Permanent permanent, Ability source, Game game) {
+        return source.getSourceId().equals(permanent.getId());
+    }
+}