They given a painting of King Denis of Portugal, We need to find the flag with given clues ,
- In Exif data of image we can find
```a3hneGs6Ly9nc3BhLnlyc3R0dy5mc3ovYWh1aW5sa2tpcmJrL2cvaS8yQ0lVQS0xekZfTk44VjZTbnZsWHo5b3JybERYMVNtYUFlUmtGQ1VhTm5nR0hTZ0dsdTNDcWhoWGhkQkZDNll5bkpoY0tEUE5TSW9UVVJnY1BGRGk4RS9jY3RreHp0```

- Decipher the base64 and use vigenere cipher with `Denis` as a key , you will get a link

```https://docs.google.com/spreadsheets/d/e/2PACX-1vS_FV8S6OantUv9bjziZK1KuxWrJsCYHsVkcTZAdCym3KnduPpaXSU6GvjWzkHZCFAFkGMZdyCXLf8A/pubhtml```

- search for user names and you will find this reddit page https://www.reddit.com/user/ThePoetDenisTheFirst/comments/p603mv/love_is_beautifull/

- with the help of the reddit Description , they mentioned as `The simple dev` contributer , search for his github page, "DenisBurgundy"
And he created the repo about the king's saint wife , finding the repo , in one of the commit , you will find another `base64`.

- now you know the flag format as `flag{DaughterName_SonName_BuriedPlace}`

- search in wiki, you can find the details asking to form a flag

**Flag**: `flag{Constance_Afonso_MonasteryofSaintDenis}`

### Writeup with detail

[Detailed writeup](https://github.com/shyamprasath18/writeups/blob/master/Jornadas%202021%20CTF/The%20Poet%20Denis%20The%20First.md)