You would start by modifying the "Monlvl" file and changing the amount of experience for each monster level (ie. a Nightmare Zombie 1 enemy is a level 36 monster and would give you 2568 experience points.) You can use the "Monstats" file as a cross reference for what level each enemy type is. I used to make mods back in the day for D2. I had a Full Sets drop mod, an XP mod, a Uniques drop mod and a Boss mod. Fun times
Forgot to mention, after you make the changes, you either need to add those modified files back to the patch file or create a subdirectory in your main D2 folder (data\global\excel) and place your modified txt file in the excel folder. Then you need to add "-direct -txt" to the Target line of the shortcut on your desktop under Properties. You have to start the game and actually load a char to have the game generate the .bin files (which you will now see in your excel folder.) Then exit the game and restart and you will see your changes have now taken effect when you start killing monsters. There may be a tool for editting the .bin file directly as I seem to remember something like that, but you'll have to check the phrozen site for that.)
Forgot to mention, after you make the changes, you either need to add those modified files back to the patch file or create a subdirectory in your main D2 folder (data\global\excel) and place your modified txt file in the excel folder. Then you need to add "-direct -txt" to the Target line of the shortcut on your desktop under Properties. You have to start the game and actually load a char to have the game generate the .bin files (which you will now see in your excel folder.) Then exit the game and restart and you will see your changes have now taken effect when you start killing monsters. There may be a tool for editting the .bin file directly as I seem to remember something like that, but you'll have to check the phrozen site for that.)
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