If you struggle to finish this game, you should unlock relics. You'll be able to access better ones during your runs. Good luck !
I did arcana and outfits first. This explains why I thought the game was so hard!
Create 20 Concoctions. - Bayonetta (Xbox 360)
Destroy all the tentacles that drop down together during in single sequence in Chapter 9. - Bayonetta (Xbox 360)
Earn Platinum Medals during Verse 1 and Verse 2 of Chapter 14. - Bayonetta (Xbox 360)