The 10X Metro Tunnels, simply 10X MTunnel, are the tunnels which they make a transportation for metro trains, the 10X MTunnels are for sale for 900 theons, the monthly price is 100 theons and it can be unlocked at the 15th rank. the 10X MTunnels are available in seven colors:
-Blue
-Green
-Yellow
-Orange
-Red
-Pink
-Purple
How to build the 10X MTunnels:
Go to Build>Transportation>Metro>10X MTunnel then you can see seven metro tunnels.
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