Here is a patch which allows you to access the debug menu after the cut-scene of Trevor Belmont in front of the cross when the game starts. It allows you to select what level, what section of that level, and which companion you wish to have with you.
May 26, 2005
I found this completely by accident! All I was gonna do was start a fresh game, But it's really cool nonetheless. Have fun with this debug code of Castlevania 3.
~Googie
Website - http://geocities.com/googitoons/romhacksmain
Message Board - http://www.googieblvd.ecwhost.com/board/
Castlevania III - Dracula's Curse (USA).nes - NOINTRO
CRC32: 7CC9C669
MD5: D16A502D0125F23CC3D980DDC6B6F2E8
SHA-1: F91281D5D9CC26BCF6FB4DE2F5BE086BC633D49B
SHA-256: 1C7B2ED2C1FB5839A6764006AA476F5C9D48F99465B6141980F3A5AF1DFEC0D6