* Activate spell's ability on the stack - fixed that it can't be activated by humans (example: Lightning Storm);

Mage.Client/src/main/java/mage/client/game/GamePanel.java

@@ -88,7 +88,7 @@ public final class GamePanel extends javax.swing.JPanel {
     private String chosenHandKey = "You";
     private boolean smallMode = false;
     private boolean initialized = false;
-    private skipButtonsList skipButtons = new skipButtonsList();
+    private final skipButtonsList skipButtons = new skipButtonsList();
 
     private boolean menuNameSet = false;
     private boolean handCardsOfOpponentAvailable = false;
@@ -102,7 +102,7 @@ public final class GamePanel extends javax.swing.JPanel {
 
     private boolean initComponents;
 
-    private Timer resizeTimer;
+    private final Timer resizeTimer;
 
     private enum PopUpMenuType {
         TRIGGER_ORDER
@@ -1289,7 +1289,11 @@ public final class GamePanel extends javax.swing.JPanel {
                 if (needChoosen.contains(card.getKey())) {
                     card.getValue().setSelected(true);
                 }
-                // play from stack unsupported
+                // users can activate abilities of the spell on the stack (example: Lightning Storm);
+                if (needPlayable.containsKey(card.getKey())) {
+                    card.getValue().setPlayable(true);
+                    card.getValue().setPlayableAmount(needPlayable.get(card.getKey()));
+                }
             }
         }
 
@@ -2537,7 +2541,7 @@ public final class GamePanel extends javax.swing.JPanel {
 
     // Event listener for the ShowCardsDialog
     private Listener<Event> getShowCardsEventListener(final ShowCardsDialog dialog) {
-        return (Listener<Event>) event -> {
+        return event -> {
             if (event.getEventType() == ClientEventType.SHOW_POP_UP_MENU) {
                 if (event.getComponent() != null && event.getComponent() instanceof CardPanel) {
                     JPopupMenu menu = ((CardPanel) event.getComponent()).getPopupMenu();

Mage.Client/src/main/java/mage/client/game/PlayerPanelExt.java

@@ -143,21 +143,24 @@ public class PlayerPanelExt extends javax.swing.JPanel {
     }
 
     private boolean isCardsPlayable(Collection<CardView> cards, GameView gameView, Set<UUID> possibleTargets) {
-        if (cards != null) {
-            // can play
-            if (gameView != null && gameView.getCanPlayObjects() != null && !gameView.getCanPlayObjects().isEmpty()) {
-                for (CardView card : cards) {
-                    if (gameView.getCanPlayObjects().containsKey(card.getId())) {
-                        return true;
-                    }
+        if (cards == null || gameView == null) {
+            return false;
+        }
+
+        // can play
+        if (gameView.getCanPlayObjects() != null && !gameView.getCanPlayObjects().isEmpty()) {
+            for (CardView card : cards) {
+                if (gameView.getCanPlayObjects().containsKey(card.getId())) {
+                    return true;
                 }
             }
-            // can select
-            if (possibleTargets != null && !possibleTargets.isEmpty()) {
-                for (CardView card : cards) {
-                    if (possibleTargets.contains(card.getId())) {
-                        return true;
-                    }
+        }
+
+        // can select
+        if (possibleTargets != null && !possibleTargets.isEmpty()) {
+            for (CardView card : cards) {
+                if (possibleTargets.contains(card.getId())) {
+                    return true;
                 }
             }
         }

Mage.Sets/src/mage/cards/l/LightningStorm.java

@@ -1,7 +1,5 @@
-
 package mage.cards.l;
 
-import java.util.UUID;
 import mage.abilities.Ability;
 import mage.abilities.ActivatedAbilityImpl;
 import mage.abilities.common.SimpleActivatedAbility;
@@ -21,11 +19,12 @@ import mage.counters.CounterType;
 import mage.filter.common.FilterLandCard;
 import mage.game.Game;
 import mage.game.stack.Spell;
-import mage.target.common.TargetCardInHand;
 import mage.target.common.TargetAnyTarget;
+import mage.target.common.TargetCardInHand;
+
+import java.util.UUID;
 
 /**
- *
  * @author LevelX2
  */
 public final class LightningStorm extends CardImpl {
@@ -38,6 +37,7 @@ public final class LightningStorm extends CardImpl {
         effect.setText("{this} deals X damage to any target, where X is 3 plus the number of charge counters on it");
         this.getSpellAbility().addEffect(effect);
         this.getSpellAbility().addTarget(new TargetAnyTarget());
+
         // Discard a land card: Put two charge counters on Lightning Storm. You may choose a new target for it. Any player may activate this ability but only if Lightning Storm is on the stack.
         SimpleActivatedAbility ability = new SimpleActivatedAbility(Zone.STACK,
                 new LightningStormAddCounterEffect(),
@@ -115,7 +115,8 @@ class LightningStormAddCounterEffect extends OneShotEffect {
         Spell spell = game.getStack().getSpell(source.getSourceId());
         if (spell != null) {
             spell.addCounters(CounterType.CHARGE.createInstance(2), source, game);
-            return spell.chooseNewTargets(game, ((ActivatedAbilityImpl) source).getActivatorId(), false, false, null);
+            spell.chooseNewTargets(game, ((ActivatedAbilityImpl) source).getActivatorId(), false, false, null);
+            return true;
         }
         return false;
     }

Mage/src/main/java/mage/players/PlayerImpl.java

@@ -44,7 +44,6 @@ import mage.game.*;
 import mage.game.combat.CombatGroup;
 import mage.game.command.CommandObject;
 import mage.game.events.*;
-import mage.game.events.GameEvent.EventType;
 import mage.game.match.MatchPlayer;
 import mage.game.permanent.Permanent;
 import mage.game.permanent.PermanentCard;
@@ -1568,7 +1567,8 @@ public abstract class PlayerImpl implements Player, Serializable {
     @Override
     public LinkedHashMap<UUID, ActivatedAbility> getPlayableActivatedAbilities(MageObject object, Zone zone, Game game) {
         LinkedHashMap<UUID, ActivatedAbility> useable = new LinkedHashMap<>();
-        // It may not be possible to activate abilities of stack abilities
+        // stack abilities - can't activate anything
+        // spell ability - can activate additional abilities (example: "Lightning Storm")
         if (object instanceof StackAbility || object == null) {
             return useable;
         }
@@ -1594,10 +1594,15 @@ public abstract class PlayerImpl implements Player, Serializable {
                 needId1 = object.getId();
                 needId2 = ((AdventureCardSpell) object).getParentCard().getId();
                 needId3 = object.getId();
+            } else if (object instanceof Spell) {
+                // example: activate Lightning Storm's ability from the spell on the stack
+                needId1 = object.getId();
+                needId2 = ((Spell) object).getCard().getId();
+                needId3 = null;
             } else {
                 needId1 = object.getId();
-                needId2 = object.getId();
-                needId3 = object.getId();
+                needId2 = null;
+                needId3 = null;
             }
 
             // workaround to find all abilities first and filter it for one object
@@ -2791,6 +2796,7 @@ public abstract class PlayerImpl implements Player, Serializable {
 
     /**
      * Return result for next flip coint try (can be contolled in tests)
+     *
      * @return
      */
     @Override
@@ -3708,6 +3714,14 @@ public abstract class PlayerImpl implements Player, Serializable {
                     UUID mainCardId = card.getMainCard().getId();
                     playableObjects.put(mainCardId, playableObjects.getOrDefault(mainCardId, 0) + 1);
                 }
+
+                // spell on stack can have activated abilities,
+                // so mark it as playable too (users must able to clicks on stack objects)
+                // example: Lightning Storm
+                Spell spell = game.getSpell(ability.getSourceId());
+                if (spell != null) {
+                    playableObjects.put(spell.getId(), playableObjects.getOrDefault(spell.getId(), 0) + 1);
+                }
             }
         }
         return playableObjects;