Lookey here

We are given a large text file called anthem.flag.txt:

$ wc -l anthem.flag.txt
    2146 anthem.flag.txt  

2146 are a lot to search the flag by hand. Instead, we can use grep to find the flag given that they have a special format format (picoCTF{...}):

$ grep picoCTF anthem.flag.txt
      we think that the men of picoCTF{gr3p_15_@w3s0m3_4c479940}