(Add this if you are publishing content) "Note: The official Neo Geo BIOS is copyrighted by SNK Corporation. It is typically extracted from original arcade boards or home consoles for backup/emulation purposes. Universe BIOS is open-source/homebrew."
Version 4.0 (now free for personal use) is the most recent major update and is widely considered essential for original hardware users. bios neo geo
It includes a massive built-in cheat engine with over 1,570 cheats , allowing for infinite lives, health, or unlocking hidden characters without external hardware. (Add this if you are publishing content) "Note:
The Unibios replaced the stock BIOS with a flashable chip that combined the functionality of both MVS and AES modes. Its features include: allowing for infinite lives