Ideally, you will want to initiate your first play through on Normal Mode to obtain Killer at the Gate of Dawn. Upon this completed play through you should have leveled up your Blood and Health to around 40-50, and obtained roughly half of your Skill Upgrades, both of which will come in handy for your Very Hard Mode play through. As well, you will want to have the Ulti-Mondo and Dark Booster costumes unlocked and equipped. I also highly recommend going ahead and rushing through a play through on Easy Mode after your Normal Mode play through, not only to obtain the AAA ranked episodes, but this will also help you grind out more Moon Crystals and Health Gems to max out your Skill and Health Upgrades.