Link: Advent Of Cyber 4 on TryHackMe
What is the Guard's flag?
First we prompt the guard.
We then search any register that was equal to the number provided.
Once we have the register we bookmark it.
We re-prompt the guard, check the value in the register, throw as-is in python, and it spits out the decimal version.
We enter this version:
The guard lets us through.
We interact again to obtain the flag:
Answer: THM{5_star_Fl4gzzz}
What is the Yeti's flag?
This time around we just look at decreasing registers.
Once we iterate, we have an arbitrarily small amount of registers.
We freeze it at 100.
We survive.
The Yeti gives us the flag:
Answer: THM{yetiyetiyetiflagflagflag}