Operation Abyss: New Tokyo Legacy

When you reach the second semester, you earn the ability to use Gamble Codes. To use a Gamble Code, go to the Development Lab, select Development and then select Affix. Instead of using a Plug-in affix, you use a Gamble Code under Key Tool. When you use a Gamble Code, you randomly get a new item that is within 3 levels higher or lower of the previous item. It is actually possible to receive the exact same item. With enough save scumming, you can get much higher leveled equipment, and this is the method I highly recommend to get the MURAMASA and the Source affixes. This should occur naturally while going for those items but you can always save and gamble 30 times for this trophy.