Board Thread:Recipe Report Board/@comment-28053036-20150921123806/@comment-26044227-20161022040110

Ofuda are the little things shown on the bottom right of your Smithing screen that you can use one time to increase the chances of getting a rare sword from that one smithing attempt. Bamboo < Plum < Pine < Fuji in terms of how much of a boost you get, but of course, no guarantees.