This is for the old cheat.dat incase others want an option for on or off instead of set.
:skullfng:00000000:0100042:00000004:00000004:Unlock Special Mode
:skullfng:00210000:010A3CD:00010001:FFFFFFFF:Unlock Special Mode
:skullfng:00000000:0100008:00000006:FFFFFFFF:Unlock Very Hard Mode
:skullfng:00110000:010A0A4:00000E6A:FFFFFFFF:Unlock Very Hard Mode
:skullfng:00000000:0100008:00000007:FFFFFFFF:Unlock Hardest Mode
:skullfng:00110000:010A0A4:00000E69:FFFFFFFF:Unlock Hardest Mode