Starting by opening challenge link http://34.69.61.54:5247/
Let's check page source
<!-- templates/index.html -->
<html>
<head>
<title>Robots Are Taking Over</title>
</head>
<body style="background-color:black;">
<center>
<h1 style="color:white">Robots are Taking Over</h1>
<img src="/static/img/robots.jpeg">
<p style="border:2px solid white; color:white">
You need to hide. They have become smarter than us.</p>
<br>
<p style=color:black">
flag.txt</p>
</center>
</body>
</html>The challenge mentien robots so let's check the robots.txt file http://34.69.61.54:5247/robots.txt
We found an interseting path
Allow: /flag/UlN7UjBib3RzX2FyM19iNGR9
If we try the check the file, we got not found. The filename is probably a base64 encoded string
Decoding UlN7UjBib3RzX2FyM19iNGR9 with base64 and we got our flag
RS{R0bots_ar3_b4d}