The S4 ICS CTF is back for S4x23. The ICS Village will run the CTF. And it will be like 9 CTFs rolled into one. The S4 ICS Capture The Flag competition was one of the first in the ICS category. My biased opinion is that Reid Wightman put on one of the most creative and challenging ICS CTFs at S4. In 2020 we stopped doing the S4 ICS CTF because they became common to ICSsec events. The impressive ICS Village was present at many events. INL, CISA and others put on ICS CTFs. Once this happens, S4 moves on to be on the bleeding edge. At S4x20 this was working with ZDI to bring Pwn2Own Miami to the ICS world.