We will finally cover the non-crypto challenges that I wrote for HKCERT CTF 2023. This includes one misc (Hackforces), two pwn (ISA Jump Scare & ISA Jogger) and two reverse (The Flag Game & Loot and Scoot) challenges.

In the last part, I will include the two non-crypto challenges I wrote for HKCERT CTF 2022: Numbers go brrr and Minecraft geoguessr.

As the third part of the series, three reversing challenges will be included: The Hardest Path, A Junior Mathematician and Let’s Chill.

I was playing Union CTF with @blackb6a last week. Since this CTF is prepared by cr0wn where Jack and hyperreality were in (they made CryptoHack), I am convinced that the CTF will be fun. Turns out I wasn’t disappointed at all. I will be writing three or four posts on the challenges, and the first of the series covers on exah, the reversing challenge I spent most of my time (yet not solving it).

This week, we have teamed up as @blackb6a to play CONFidence 2020 CTF. We end up ranked 15, but we are more proud of ourselves able to solve a reversing challenge called Team Trees (395 points, 5 solves).

In particular, we are the first-to-solve to the challenge. It took us around two hours to win the flag. This writeup is written by @harrier_lcc and @mystiz613.

A Plaid Puzzle is a RPG game written in PuzzleScript. In the game, you are able to control as the player and you could move around and mess with a string. The game is available online on PuzzleScript.net.