Not gonna lie it's a grind BUT~~ it's an easy as fuck grind. Basically kill mobs to spawn fates, kill fate bosses to gain loads of exp and crystals, get to level 18-20 and kill the main boss Pazuzu to get feathers. If you die and don't get rez'd within 10 minutes you lose a level. It took my GF about 3 days to get 2 Eureka Relics.