Before you start experimenting in your item.dat file, open the flame forge in toribash. mess with the settings and once you are satisfied with your flame, write down the stats and copy them in to a duplicate item.dat file. MAKE SURE THEY ARE MAPPED IN THE CORRECT SPOTS! Keep this separate item.dat file in your custom folder and save it as "item1.dat" or something else of your choosing. whenever you want to have a flame in single player, save "item1.dat" as "item.dat" and turn off your internet. If your internet is on then it will update your items and the flame will dissapear. you could also just copy the item.dat with the flame into another users file and just /lp them.
You might want to add this in magix. But maybe reword it so that people don't die of old age when they are halfway through.