Hello,

I’m excited to share a KataGo fork trained for large boards (up to 50x50!), developed with guidance from lightvector (KataGo’s creator). After a year of training - mixing 85% standard 19x19 selfplay and 15% large-board games (that I generated) - this network achieves remarkable results!

Key Strengths (100 visits, balancing speed vs reliability):

• 19x19:
  • +50 Elo vs initial network (kata1-s7503 from Sept 2024).
  • Only ~30 Elo weaker than the current best network (as of May 2025)!
• 25x25:
  • +200 Elo vs kata1-s7503 and +400 Elo vs kata1-s8656 (which is weaker on large boards)
• 29x29:
  • Large dominance: ~+500 Elo vs kata1-s7503 | ~+900 Elo vs kata1-s8656!
• 37x37 to 50x50:
  • Standard kata1 networks are almost unable to play, hence no comparison is possible
  • But LB-networks gained +800 Elo during training vs an early Oct 2024 network (which already crushed KataGo 100% of the time on 37x37).

Cool Findings:

• Komi Stability: Japanese rules komi stays at 6.0 from 9x9 to 50x50!
• Opening Moves:
  • Identical preferences to kata1 on 19x19 (4-4, 4-3, etc.). Hence, no "surprising preferred moves" such as 5-4, 6-4 or even 10-10 move! That would have been funny, but no, that's not the case.
  • On 50x50, 4-4 and 4-3 remain top moves, but 5-3, 5-4, 3-3 and even 11-4 are close contenders (only 1% to 1.8% winrate difference).

Try It Yourself:

• Download: https://katagotraining.org/extra_networks/, see "Large Board" section)
• Some more technical details: https://www.lifein19x19.com/viewtopic.php?p=281790#p281790

Why This Matters: If you’ve ever wanted to play serious AI Go on absurdly large boards, this is your chance! The network retains 19x19 strength while crushing KataGo on larger sizes.

Big thanks to lightvector for the mentorship — this wouldn’t exist without his help!
Questions? Ask away, I’ll be happy to give some more details 😊

Friday9i