u can learn all the ronso rages from biran and yenke except for nova. n u can only get white wind and mighty guard after they have used it themselves

the crest is hidden between some pillars on the left just after the point wer u fought seymour flux on mt.gagazet.

to get the weapon, activate 3 cactuars stones in the tunder plains (with square) then go to the south end of tunder plains south and u'll find a ghost of a cactuar. follow it to a wrecked lightning conductor and press square again