Art

We are given a PNG image called art.png:

$ file art.png
art.png: PNG image data, 300 x 300, 8-bit/color RGBA, non-interlaced  

We might think that the flag is somehow encoded in the colors that appear in the image. Actually, after a bit of research, we can find out that there is an esoteric language called npiet that encodes text in images with colors:

The examples look similar to what we have, so let’s try it:

And there’s the flag: HTB{p137_m0ndr14n}.