I did him with a 100% cold daisho, just use feint when you hear him make the earthquake sound and keep an eye on the buff icon, so you don't miss the recast after 6 seconds when feint runs out.....this propably takes a bit longer then with armor ignore but you get a lot less damage from him. As for the mods you should imbue, that depends on your temp. If your low on stam > then 180 I would advice on Dragon Slayer,SSI 30, SL 50, 50-60 ML, rest in damage. If your fast enough with then exchange SSI with HLA.