Ragnar & Lagertha are two secret agents of Valhalla wants to share a secret message but could not place the trust on basic ciphers so they decided to come up with their own cipher

We have managed to get the ciphertext
:082_336_88_167755403.
So help us and we will reward you with 50 points
Flag is not wrapped in xiomara
so submit in xiomara{youranswer}

finalhen.txt

Let’s check the given txt file first.

So, we need to solve the alphametic puzzle first to retrieve the letters of ciphertext. Also, notice that underscores are ignored both calculating the size and the position in the example given. There are lots of websites that solve alphametic puzzles. Let’s use one of them and retrieve the solution.

Now, we can convert the numerical cipher to alphabetical cipher.

Now, we need to right shift every character by (position * size) % 26.

Here is the python script I created for the task.

Let’s run the script and get the flag.

Here is the flag xiomara{THE_ARS_OF_DIDUCTION}.