Update 8.1 alpha

[h2]CHANGE LOG[/h2]

Corrected mistakes

• Water returned to the lower level in the location with the tunnel.
  
• Fixed the name of the door with a large window.
  
• Fixed a bug in which, if the character had great physical strength, the arrow flew through the zombies.
  
• Now burning iron barrels are detected as iron objects.
  
• Fixed a bug where the zombie nurse got stuck in a dead end in the tunnels.