When I did my first CTF, it was close to the deadline and I thought I had the extracted the flag from the program and the rest of the program was just filler, so I entered the flag, and it told me it was not the flag. It turns out the program multiplies the input by a pseudorandom matrix before comparing it against the flag, so I had to implement a matrix inversion and then get the flag. That's not the story though.

The matrix was always the same and the challenge was clearly designed so that the point was being able to read anything at all, not knowing how to invert a matrix, so I asked the creator what was up.

He told me that there were tools that would trace input values until they reached a comparison instruction, then print what they were compared against. Therefore it was necessary for every deobfuscation challenge to scramble the input in some way too complex for these tools to undo, before comparing it. Hence the multiplication by a pseudorandom matrix.

The point is, cheating tools aren't new.