Based around the concept of Free Knight Parn after obtaining the Sword of Valis (a sword which can cleave ghosts). If you change the equipment (such as heavier sword, armour, etc) then you'll need to change up the RFP with the Havel's Ring (which of course means losing out on the bonuses you get for the RFP). The secondary ring slot is left blank to allow for flexibility (such as when battling the Four Kings) and you can swap this out with any ring of your choice (I might suggest the Chloranthy Ring for typical play).
