Ad frequency reduced

Assets/Darkmatter/Code/Features/ColorbookFlow/System/ColorbookFlowController.cs

@@ -28,6 +28,7 @@ public class ColorbookFlowController : IAsyncStartable, IDisposable
     private IDisposable _selectedSub;
     private IDisposable _returnToMainMenuSubscription;
     private bool _navigatingToGameplay;
+    private int _selectCount;
     private CancellationTokenSource _scopeCts;
 
     public ColorbookFlowController(
@@ -110,9 +111,14 @@ public class ColorbookFlowController : IAsyncStartable, IDisposable
         _loadingScreen.Show();
         _loadingScreen.SetProgress(0f);
 
-        // Fire the interstitial but never await it: the ad overlays the transition while the level
-        // loads underneath, so a missed/dropped ad callback can't stall the flow at 0% anymore.
+        // Frequency cap: show an interstitial on every 2nd level open (2nd, 4th, ...). On skip turns
+        // just keep one prewarmed so the next show has an ad ready. Fire-and-forget either way — the
+        // ad overlays the transition while the level loads underneath, so a missed/dropped ad callback
+        // can't stall the flow at 0% anymore.
+        if (++_selectCount % 2 == 0)
             ShowInterstitialAdAsync(ct).Forget();
+        else
+            PrewarmInterstitialAdAsync(ct).Forget();
 
         try
         {