Beat it in normal, as Richter, and with low stats. Richter's can be done fairly quickly, just ignore all optional bosses and aim for the final boss. You dont level up as Richter or get any new equipment. If you do go all out around the castle just grab a Holy water sub-weapon and never let go of it.
The low stat run, just get any equipment you can that raises defense, the only stat you have that is useful in this run is Luck which is 30 so you will crit a lot. Once you find the large gold skeletons kill them till you get 2 rings of varda and you're pretty much set.