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}

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