Australia - The Secret Message

Solution

A zip file containing a message.txt was given. The zip file contained an encoded string starting with revrs.
The string ended with srver which was the reverse of revrs, so we understood that revrs at the beginning meant to reverse the string.
When we reverse the code leaving back revrs at the start, we again have a revrs which meant to reverse it again. And then we saw bas64 at the beginning of the string.
We understood it should be decoded with base64 and once we did that, we also observed we got a rot13.
For the uninitiated, rot13 is simple letter substitution cipher that replaces a letter with the 13th letter after it. All this can be done with any online decoder website.
As we decode in recursion, the string gets smaller and smaller until we get the flag.
If we observe, all the operations are mentioned in 5 characters making it easier to write a program to decode this.
We will have to iterate till we do not find revrs or bas64 or rot13 and do the operation in the first 5 characters in the string. The end result would be the flag