• Thanks to your feedback we recentrly found out that you cannot progress after level 21 after completing it untill you launch the map again (go to Castle and press Game once again).
  It was fixed in this patch.
  
• removed end-game music playing in wrong level
  
• adjusted the scale of cave-rocks on table in 21 level that could prevent enemies from walking
  
• fixed Arena achievement
  
• all navigation for ai was rebuild.
  

P.S.: 24-Jan-addition - if your Castle health is zero and you have no money to restore you couldn't start the wave but the table showed that the wave is running. It was fixed.