From Before I Play
- Chakrams are awful and you'll probably find yourself not using them outside of the times when the game actively forces you to. This is normal, and upgrading them won't make them any better.
- You will need all the weapons to unlock Branch D and the true final boss. There are a few hidden in side missions, but the majority of them will come from chests inside the levels or from the shop.
- And speaking of the shop, the weapons in there get incredibly expensive, and you will have to grind in order to buy out the last few. If you're committed enough to actually go for Ending D, just save yourself the trouble and buy the DLC for your favorite sister and play that. Not only will it give you a little more backstory on them, but each one has about 500,000 Gold up for grabs. Two's and Four's are generally accepted to be the best of the bunch, although One's and Five's aren't too bad if you don't mind using Chakrams/Lances respectively. Stay away from Three's altogether unless you really, really like her as a character because her DLC is really bad.
- With the exception of Zero's, you should be able to play the DLC without fear of spoilers after Ending A. Zero's touches on stuff that doesn't come up until Ending D, and should be saved until right before the final boss or after clearing it.