Looking at the file using a hex editor or using binwalk to extract everything, you'll see a link to [https://pastebin.com/wR7uvAyw](https://pastebin.com/wR7uvAyw), which contains an encrypted ciphertext.

No, it's not base64 but actually base32.

Decoding it you'll get: `drrepv{uk5t_awttt5_cic_pp35wu3}`

Here it's obvious that the plaintext should be `batpwn{something`}, and trying some simple ciphers you'll get it fully decrypted using Vigenere with the key `cryptii` (as provided in the challenge description).

Flag: `batpwn{mi5c_chall5_are_aw35om3}`