This Question is an example of Extended Ceaser cipher( Shift cipher ) , the original Ceaser cipher had key 3 but extended Ceaser can have any Unknown key.
Lets Start . Decrypt the below link , Solve the mystery and go on.
nuf.xk/eturfoubtqdbmdf2
Answer will be Found after three Rounds , and will be Numeric .
Assumptions Shift only applies to alphabets . Numbers Stays Same
Example
Plain text = "abc123"
Key=2
Cipher text = "cde123"
by
Dilroop Singh