by Jair from the Vale
You can hack your saved games from Seiken Densetsu 3 in any hex editor. I recommend Hex Workshop. [romname].srm is your saveram file; it should be 8KB in size.
All addresses and numbers in this document will be in hexadecimal (base 16), so make sure you understand that before continuing. If you don't understand hexadecimal or hex editing, you may want to read my Basic Hex Tutorial first.
What's in here:
Quick start (see below) Instructions for fixing the checksum HP, MP, stats, experience Equipment Magic Class Counter gauge maximum Luc Item ring Item storage
What's not but hopefully will be someday:
Character Which sets of equipment the darn shops sell you Save point Any other interesting things I discover
Open your saveram file in your hex editor. SD3 has three save logs; each one takes up 800h bytes. The first 70h bytes, from 0 to 6F, are a kind of header -- it's the info that appears on the save / load screen, and has no effect on your actual game.
All addresses in this document will be for log 1; if you want to hack log 2, add 800h; if you want to hack log 3, add 1000h. For example, maximum MP for character 1, log 1 is at 1FF. Max MP for character 1, log 2 is at 9FF. Speaking of maximum MP, let's hack that right now, so you can get the hang of hacking saverams. If this is old hat to you, go ahead to the other sections.
Scroll down to address 1FF in your hex editor. In my saveram, my first character has a max MP of 3E (that is, 62 decimal). Whatever that value is, increase it by one. Example: mine is 3E now, so I'll change it to 3F.
Save it, start up SD3, and try to load your game. But wait, what's this? It says that save file doesn't exist. This is because each save log has a checksum at the end. This will be explained in detail in the next section. For now, scroll way down to address 7FE.
You increased your max MP by one, so you have to increase the checksum by one. Whatever the 2-byte value is at 7FE-7FF, increase it by one. Example: mine is C24C, so I'll change it to C34C. (Not C24D! Remember, values are always in reverse byte order.)
Save it, start up SD3, and load your saved game. Check the subscreen, and your max MP should be one higher than it was. You're off and running!