DEF CON 24 0x20th Anniversary Core War Competition

Core War 0x20 LogoWHAT: A programming game
WHEN: Friday and Saturday, 1200 to 1500 – Go to

It’s been 32 years since the invention of Core War, the ultimate programming game, and this year at DEF CON hackers from around the world will be submitting their programs to contend in a fight to the crash in cyberspace.

For those who don’t know, Core War is a game in which assembly language programs run on a simulated computer, competing to see which one can survive to the end.

If you have never played Core War before, never fear! It’s not difficult at all to learn, especially if you understand a little about assembly language programming already. Check out this tutorial to get started.

Hill rules are:

ICWS I994 extensions enabled
Core size: 8000 cells
Cycles to completion: 80000 cycles
Maximum number of processes: 8000 processes
Maximum warrior length: 100 instructions
Minimum distance between warriors: 100 cells
PSPACE enabled
2 games of 50 rounds each per warrior pair

If you would like to test your warriors with these conditions in pMARS, use the command line settings: pmars -p 8000 -c 80000 -p 8000 -l 100 -d 100

Please test your warriors on the pMARS before submitting them. Submissions that fail to parse or fail to assert will be rejected. During the tournament, all combinations will be run (every warrior will face every other warrior) and the score will be calculated as Wins + (Ties/4).

We will run two separate competitions, one on Friday and one on Saturday. Several practice rounds will occur each day before the official qualification, semifinals, and finals rounds.



  1. In the Contests room next to Forensics CTF and around the corner from Scavenger Hunt