Hint

06 - Witchcraft
I was just messing around with my magic wand trying out some new spells and all of a sudden the flag was gone.

All I was left with is the following:

    363336643331333832643438363537373432326436383530
    333137323264346337393738333932643635373035343465

Can you undo my spell and get the flag?

Approach

The first thing that jumped out to me on this one is the number of 3s in the text. Obviously this is some sort of encoded string. Taking the first few bytes 36 33 as hex numbers and convert them to a string 63. 63 is the ascii code for c and since I knew all of the flags started with cm, I definitely had a lead.

I wrote a small script to process through the entire string:

static void Main(string[] args)
{
    var input = "363336643331333832643438363537373432326436383530333137323264346337393738333932643635373035343465";
    Console.WriteLine(HexToString(input));
    Console.WriteLine(HexToString(HexToString(input)));
    Console.ReadLine();
}

static string HexToString(string source)
{
    StringBuilder sb = new StringBuilder();
    for(int i=0; i<source.Length; i+=2)
    {
            sb.Append(Convert.ToChar(int.Parse( source.Substring(i, 2), System.Globalization.NumberStyles.HexNumber)));
    }           return sb.ToString();
}

This yields the output:

636d31382d486577422d685031722d4c7978392d6570544e
cm18-HewB-hP1r-Lyx9-epTN

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