From 655625d695df355ec2b7db90fe10113a9ec9be24 Mon Sep 17 00:00:00 2001
From: Oleg Agafonov <jaydi85@gmail.com>
Date: Sun, 18 May 2025 20:44:46 +0400
Subject: [PATCH] Gavi, Nest Warden - fixed game error on usage

---
 Mage.Sets/src/mage/cards/g/GaviNestWarden.java     | 14 +++++++++-----
 .../abilities/effects/CostModificationEffect.java  |  2 ++
 2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/Mage.Sets/src/mage/cards/g/GaviNestWarden.java b/Mage.Sets/src/mage/cards/g/GaviNestWarden.java
index d3b160ea39d..2a44541ccc5 100644
--- a/Mage.Sets/src/mage/cards/g/GaviNestWarden.java
+++ b/Mage.Sets/src/mage/cards/g/GaviNestWarden.java
@@ -93,13 +93,17 @@ class CyclingZeroCostEffect extends CostModificationEffectImpl {
     @Override
     public boolean apply(Game game, Ability source, Ability abilityToModify) {
         Player player = game.getPlayer(source.getControllerId());
-        if (player == null || !player.chooseUse(outcome, "Pay {0} to cycle this card?", source, game)) {
+        if (player == null) {
+            return false;
+        }
+        if (game.inCheckPlayableState() || player.chooseUse(outcome, "Pay {0} to cycle this card?", source, game)) {
+            abilityToModify.clearManaCostsToPay();
+            abilityToModify.getCosts().removeIf(cost -> !CyclingDiscardCost.class.isInstance(cost));
+            abilityToModify.addManaCostsToPay(new GenericManaCost(0));
             return true;
         }
-        abilityToModify.clearManaCostsToPay();
-        abilityToModify.getCosts().removeIf(cost -> !CyclingDiscardCost.class.isInstance(cost));
-        abilityToModify.addManaCostsToPay(new GenericManaCost(0));
-        return true;
+
+        return false;
     }
 
     @Override
diff --git a/Mage/src/main/java/mage/abilities/effects/CostModificationEffect.java b/Mage/src/main/java/mage/abilities/effects/CostModificationEffect.java
index fa8f7b9b866..07412e7ed35 100644
--- a/Mage/src/main/java/mage/abilities/effects/CostModificationEffect.java
+++ b/Mage/src/main/java/mage/abilities/effects/CostModificationEffect.java
@@ -21,6 +21,8 @@ public interface CostModificationEffect extends ContinuousEffect {
     /**
      * Called by the {@link ContinuousEffects#costModification(java.util.UUID, mage.abilities.Ability, mage.game.Game) ContinuousEffects.costModification}
      * method.
+     * <p>
+     * Warning, choose dialogs restricted in plyable calculation, so you must check inCheckPlayableState
      *
      * @param game The game for which this effect should be applied.
      * @param source The source ability of this effect.